谷轮ZW系列(中间补气涡旋)压缩机应用指南
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涡旋压缩机的使用涡旋压缩机的工作原理是通过转子的旋转运动将气体吸入机内,然后压缩气体,并将其排出。
涡旋压缩机通常由一个主转子和一个从转子组成。
主转子是一条螺旋线形状的曲线,通常被称为蜗杆,而从转子是一个外形与主转子相似的曲线。
主转子和从转子通过齿轮等机械装置连接并驱动,使得从转子沿着主转子旋转。
1.结构简单:涡旋压缩机的结构相对简单,由于没有需要冷却和润滑的活塞引擎,因此减少了一些机械故障和维护成本。
2.体积小:相对于其他类型的压缩机,涡旋压缩机的体积较小,因此占用的空间较小,适用于空间有限的场所。
3.低噪音:涡旋压缩机的工作过程相对较平稳,因此产生的噪音较低。
这对于需要安静工作环境的场所是一个优势。
4.运行稳定:涡旋压缩机由于没有冲击和振动,因此在运行过程中比较稳定,容易实现自动化控制。
除了以上的优势之外,涡旋压缩机还有一些需要注意的使用事项:1.需要润滑:涡旋压缩机的转子与内腔之间存在间隙,因此需要使用润滑油进行润滑。
在使用涡旋压缩机之前,需要检查润滑油的量和质量,并及时添加和更换。
2.温度控制:涡旋压缩机在工作过程中会产生一定的热量,因此需要采取适当的措施来控制温度。
可以使用风扇、散热片、冷却水等方法来降低温度。
3.定期维护:涡旋压缩机需要定期检查和维护,包括清洁滤芯、检查和更换密封件、检查电机和控制系统的正常运行等。
总之,涡旋压缩机作为一种常见的压缩机类型,具有广泛的应用和一些特点优势,但在使用过程中也需要注意一些事项。
在正确使用和维护的前提下,涡旋压缩机可以有效地提供压缩气体,满足各种使用要求。
目录No.:00000000000000411.热力学计算 (1)2.动力计算 (5)3.结构尺寸设计 (18)4.参考文献 (30)5.实践心得 (31)1.热力学计算 已知条件有: 相对湿度φ=0.8 空气等熵指数k=1.4 第一级吸气温度Ts1=40℃ 第二级吸气温度Ts2=40℃ 额定排气量Qd=0.6m 3/min 额定进气压力Ps1=0.4MPa 额定排气压力Ps2=2 MPa压缩机转速取n=1000r/min ,活塞行程S=2r=100mm 。
活塞杆长度500mm ,曲柄长度r=50mm 。
1.1行程容积,气缸直径计算 ① 初步确定各级名义压力根据工况的需要选择计数为两级,按照等压比的分配原则,12εε===2.828但为使第一级有较高的容积系数,第一级的压力比取稍低值,各级名义压力级压力表如下:级数ⅠⅡ吸气压力p s 0/MPa 0.4 0.8 排气压力p d 0/ MPa 0.8 2 压力比ε0= p d 0/ p s 022.5② 定各级容积系数Ⅰ.确定各级容积系数。
取绝热指数为K=1.4,取各级相对余隙容积和膨胀指数如下:1α= 0.11 2α=0.13 1m =1.3 2m =1.35 得 :1/m1v11111λαε=--() λv2=0.874 =1-0.11x(21/1.3-1) =0.92Ⅱ.选取压力系数: p1λ=0.97 p2λ=0.99 Ⅲ.选取温度系数: t1λ=0.95 t2λ=0.95 Ⅳ.选取泄露系数: l1λ=0.92 l2λ=0.90 Ⅴ.确定容积效率: V v p t l ηλλλλ= 得:V1η=0.78 V2η=0.74③ 确定析水系数ϕλ第一级无水析出,故1ϕλ=1.0。
而且各级进口温度下的饱和蒸汽压sa p 由文献查的1t =t 2=40℃ P sa =7375Pa得:()2s11sa11s22sa2p p /p p ϕλϕεϕ=--()=(4 105-0.8x7375)x2/(8x105-7375) =0.98④ 确定各级行程容积s1v v1V q /n η==0.6/(1000x0.78) =0.00077 m 3s2v s122s21V2V (q p T )/(np T )ϕλη==(0.6×105×313×0.98)/(1000×8×105×313×0.74) =0.0004 m 3⑤ 确定气缸直径,行程和实际行程容积 已知转速n=1000r/min 。
压缩机的配置所有谷轮半封闭压缩机均设了滤油网,加油孔,带有压力表接口的排气和吸气截止阀,吸气过滤网及视油镜。
谷轮半封闭回气冷却型压缩机(以及LA60型空气冷却压缩机)安装了带有针型阀油压检测接口的油泵强制润滑油系统,可以连接机械式油压差控制器,其中S系列压缩机可使用电子油压差控制器。
油泵强制润滑油系统必须使用油压差控制器监控油压。
谷轮半封闭压缩机电机覆有防止润滑油和制冷剂渗透的绝缘层。
电机定子被压入机体,转子则直接固定在压缩机主轴上。
电机的冷却极为重要,因为它直接影响压缩机的使用寿命。
一般而言,电机绕组最适合的温度为70 C至90 C,最高不能超过100 G电机的承载能力取决于它的运转温度,如果绝缘层承受的温度过高,电机就可能损坏。
电压过度波动,缺相,电机堵转及散热效果不良都可增加额外功耗,从而使电机温度急剧上升。
每台压缩机都带有电机保护装置以保证在极端工况时电机的安全使用。
压缩机的冷却风冷压缩机可由冷凝器风机的空气流冷却,也可采用有足够风量的独立的风机冷却;冷却风必须要直接吹向压缩机。
回气冷却型压缩机在回气冷却压缩机中,电动机被经过定子和转子间的气态制冷剂冷却。
回气冷却压缩机中电机的热量由流经内置电机的制冷剂蒸汽带走•由于回气密度随着蒸发温度降低而减小,气体在压缩前的温度将因电机热而过度上升•进入吸气腔较高温度的气体再加上压缩热,将引起排气温度过高•因此在某些应用场合,必须用一个垂直安装的风量为328.5米/分的风机冷却汽缸头。
在R22 低温应用时,通常用附加喷液冷却来保证排气温度在允许的范围之内。
排气温度过高将产生一系列的问题,例如引起润滑油变质或形成酸性物质,从而引发电机或轴承的故障。
蒸发温度越低,排气温度就越高。
为了防止过高的排气温度,应使压缩机运行在相应于不同的制冷剂的规定使用范围内。
对于使用R22制冷剂并且蒸发温度低于-20oC的S系列半封闭压缩机,采用强制冷却系统(DTC阀喷液冷却系统),这是一种防止排气温度过高的有效措施。
.压缩机的配置所有谷轮半封闭压缩机均设了滤油网,加油孔,带有压力表接口的排气和吸气截止阀,吸气过滤网及视油镜。
谷轮半封闭回气冷却型压缩机(以及LA60型空气冷却压缩机)安装了带有针型阀油压检测接口的油泵强制润滑油系统,可以连接机械式油压差控制器,其中S系列压缩机可使用电子油压差控制器。
油泵强制润滑油系统必须使用油压差控制器监控油压。
谷轮半封闭压缩机电机覆有防止润滑油和制冷剂渗透的绝缘层。
电机定子被压入机体,转子则直接固定在压缩机主轴上。
电机的冷却极为重要,因为它直接影响压缩机的使用寿命。
一般而言,电机绕组最适合的温度为70 C至90 C,最高不能超过100 C。
电机的承载能力取决于它的运转温度,如果绝缘层承受的温度过高,电机就可能损坏。
电压过度波动,缺相,电机堵转及散热效果不良都可增加额外功耗,从而使电机温度急剧上升。
每台压缩机都带有电机保护装置以保证在极端工况时电机的安全使用。
压缩机的冷却风冷压缩机可由冷凝器风机的空气流冷却,也可采用有足够风量的独立的风机冷却;冷却风必须要直接吹向压缩机。
回气冷却型压缩机在回气冷却压缩机中,电动机被经过定子和转子间的气态制冷剂冷却。
回气冷却压缩机中电机的热量由流经内置电机的制冷剂蒸汽带走.由于回气密度随着蒸发温度降低而减小,气体在压缩前的温度将因电机热而过度上升.进入吸气腔较高温度的气体再加上压缩热,将引起排气温度过高.因此在某些应用场合,必须用一个垂直安装的风量为 328.5米 /分的风机冷却汽缸头。
在R22低温应用时,通常用附加喷液冷却来保证排气温度在允许的范围之内。
排气温度过高将产生一系列的问题,例如引起润滑油变质或形成酸性物质,从而引发电机或轴承的故障。
蒸发温度越低,排气温度就越高。
为了防止过高的排气温度,应使压缩机运行在相应于不同的制冷剂的规定使用范围内。
对于使用R22制冷剂并且蒸发温度低于-20oC的S系列半封闭压缩机,采用强制冷却系统(DTC阀喷液冷却系统),这是一种防止排气温度过高的有效措施。
采用先进的技术致力于为客户提供世界级的产品艾默生环境优化技术在家用、商用和工业应用方面,是世界领先的供热、通风、空调和冷冻解决方案提供商,我们为客户提供先进的技术解决方案、完善的技术支持和培训服务。
从20世纪40年代的第一台半封闭式压缩机和20世纪50年代的全封闭式压缩机,从20世纪80年代的高效Dicus 半封闭压缩机和20世纪90年代的空调和制热用涡旋压缩机,到今天最新的Stream半封闭压缩机以及数码涡旋压缩机,在过去的80多年里,我们向市场引入了众多的创新科技。
不仅如此,我们还为空调和冷冻市场提供非同一般的解决方案。
艾默生环境优化技术是空调和冷冻业界主要的解决方案提供商,旗下的谷轮品牌产品提供了多种多样的解决方案:从主要冷媒都适用的涡旋和半封闭压缩机,到可变能力输出调节的压缩机以及装备了智能电子控制元器件的压缩机,艾默生环境优化技术引领压缩机科技发展至新的高度。
我们的使命:我们是理想的业务伙伴我们是技术领域的领袖我们能够创造最卓越的价值我们能够提供综合性解决方案我们能够创建一个安全可靠、让人们安居乐业的美好环境目录概述涡旋制热的优点型号说明压缩机配置说明应用范围制热量 - 50 Hz 制热量 - 60 Hz 技术参数 - 50 Hz 技术参数 - 60 Hz 外形尺寸联系方式01 02 02 02 03 04 22 27 30 31 53谷轮涡旋™ ZW热泵热水专用压缩机相对于使用电加热器或燃料锅炉来加热热水和室内供暖,谷轮涡旋™ ZW压缩机具有更高的能效比。
艾默生环境优化技术拥有1亿台涡旋压缩机的生产及应用经验,其可靠性和高效性已被广泛认可。
在此基础上,ZW热泵热水专用压缩机采用了Scroll Heating™ (涡旋制热)技术以及多种新型产品设计特征,具有其特有的专利技术。
涡旋制热技术将热泵热水器制热范围可靠地扩展至-20°C的环境温度,并将制热能力提高约40%,能效提高22%。
zw热泵热水压缩机使用说明概述说明以及解释1. 引言1.1 概述本文旨在介绍zw热泵热水压缩机的使用说明,在这一部分我们将概述文章的内容和目的。
zw热泵热水压缩机是一种先进的设备,可通过压缩和循环过程将低温热能转化为高温热能,实现节能减排的效果。
本文中将详细介绍该压缩机的工作原理、使用注意事项以及其优势与应用范围。
1.2 zw热泵热水压缩机简介在本节中,我们将对zw热泵热水压缩机进行简要介绍。
zw热泵热水压缩机是一种采用先进技术制造的设备,它采用了高效率的压缩机和循环系统,可以高效地将低温热源转换为高温供暖或生活用水。
该压缩机具有节能、环保、稳定性好等特点,被广泛应用于工业和民用领域。
1.3 目的本文旨在向读者提供关于zw热泵热水压缩机使用方面的说明和指导。
通过深入了解该设备的工作原理和使用注意事项,读者将能更好地了解并正确操作zw热泵热水压缩机。
此外,我们还将通过对该设备优势与应用范围的介绍,展示其在节能减排和环保方面的重要作用,并对未来的发展前景进行展望。
以上是本文“1. 引言”部分的详细内容。
通过该部分的阐述,读者可以清晰地了解到文章的概述、zw热泵热水压缩机简介以及本文的目的所在。
2. zw热泵热水压缩机工作原理:2.1 原理概述zw热泵热水压缩机是一种利用压缩机工作原理和热泵循环过程来实现高效加热的设备。
它通过对低温的外部环境空气或废热进行吸收,然后通过压缩传递给高温介质,使其温度升高。
该设备采用闭式循环系统,通过不断循环运行中的蒸发、压缩、冷凝等过程,实现能量的转换和传递。
2.2 压缩机工作流程zw热泵热水压缩机的工作流程主要包括四个步骤:蒸发、压缩、冷凝和膨胀。
首先,在蒸发器中,低温的环境空气或废热进入到设备中与制冷剂进行换热。
在这个过程中,制冷剂从液态变为气态,并吸收外部环境的热量。
接着,在压缩器中,制冷剂被压缩成高温高压气体。
在这个过程中,制冷剂的压力和温度都明显提高。
然后,高温高压气体进入到冷凝器中,在与热水或其他介质进行换热时,制冷剂释放出吸收的热量,并转变为液态。
谷轮涡旋压缩机应用广东西屋康达空调有限公司2006年9月一、谷轮涡旋压缩机介绍V主要机型系列V内部结构V涡旋压缩机工作原理V谷轮柔性涡旋压缩机特性---径向柔性V谷轮柔性涡旋压缩机特性---轴向柔性主要机型系列内部结构涡旋压缩机工作原理谷轮柔性涡旋压缩机特性---径向柔性Scroll Scroll Scroll 径向柔性666杂质•确保涡旋盘接触但是允许涡旋盘向一侧分离从而使杂质和液体通过而不至损坏涡旋盘谷轮柔性涡旋压缩机特性---轴向柔性V维持涡旋盘端面恒定、均匀的压力V浮动密封是关键a 优化端面负荷a 维持压力平衡a 消除泄漏a专利设计上涡旋盘(静盘)浮动密封下涡旋盘(动盘)二、谷轮涡旋压缩机应用要点V主要部件及保护的应用V系统设计其他考虑因素(一)、主要部件及保护的应用V气液分离器V曲轴箱加热器V排气温度保护V高低压保护V电机保护V吸排气消音器气液分离器的应用V气液分离器的应用考虑-气液分离器的回油孔和过滤网的合理设计对液体制冷剂和油的控制非常重要-一般空调系统回油孔径1.6~3.2mmQUNTUM/QUEST:1.0~1.4mmSUMMIT:1.0~1.9MM,SPECT/LCS:1.8~2.3mm-回油孔应带滤网30x30mesh(0.6mm开孔)-一定要注意气液分离器的进出管方向过量连续回液试验V过量连续回液试验:在低温环境下运行热泵工况,使系统出现稳定状态的回液-工况为室内21°C ,室外低到极限(-18°C或更低)-断开除霜控制,必要时向室外盘管喷水-记录吸排气温度和压力(离管口6inch/150mm)和油槽温度(底部中间)-如果系统现场充注,应增加15%充注量V结霜运行数小时使饱和吸气温度降到-23°C或更低,油槽温度应高于下图所规定的值过量连续回液试验一般认为,在空调应用中,油槽温度比蒸发温度高15℃以上是安全的曲轴箱加热器的应用V加热器在压缩机停机时应保持通电V现场初次启动前或长时间停机后再启动应通电12~24小时-避免初次开机时油被稀释和轴承应力过大-若12小时不可行,可采用以下技巧A、由一500W灯泡或其他安全热源在机壳底侧,使底部的液体在启动前被蒸发B、用人工方式直接将压缩机通电一秒钟,间隔5秒后再通电一秒钟。
涡旋式空气压缩机安全操作规程
1. 引言
该安全操作规程适用于涡旋式空气压缩机的操作和维护。
本规程的目的是确保操作人员的安全,并保护设备的正常运行。
2. 操作前的准备
在操作涡旋式空气压缩机之前,操作人员应确保以下准备工作已完成:
- 检查压缩机周围的环境是否安全,并清除任何障碍物。
- 检查压缩机的电源是否连接稳定,并确保接地良好。
- 检查涡旋式空气压缩机的相关润滑油是否充足。
3. 涡旋式空气压缩机的操作步骤
按照以下步骤操作涡旋式空气压缩机:
1. 打开压缩机的电源开关。
2. 观察压缩机的运行状态,确保其正常启动。
3. 根据具体需求调整压缩机的压力和流量。
4. 按照规定的时间间隔,对压缩机进行定期的维护和检查。
4. 涡旋式空气压缩机的安全注意事项
在操作涡旋式空气压缩机时,操作人员应遵循以下安全注意事项:
- 禁止在操作过程中摆放易燃物品。
- 当涡旋式空气压缩机运行时,禁止触摸其旋转部件。
- 在进行维护和检修时,必须先切断电源并等待机器完全停止后再操作。
5. 应急处理措施
在发生紧急情况时,操作人员应立即执行以下应急处理措施:- 快速切断电源。
- 疏散附近的人员并呼叫急救人员。
- 如果有火灾,尽量用灭火器扑灭,切勿用水。
6. 结论
通过遵守本安全操作规程,可以有效降低涡旋式空气压缩机操作过程中的风险,并确保操作人员的安全。
同时,在使用涡旋式空气压缩机时,操作人员还应参考相关操作手册和厂家提供的安全指南。
涡旋压缩机应用手册AE-1303-R4ZR84KC --ZR144KC应用指南前言本手册叙述了7~12冷吨R22/R407CSUMMIT谷轮涡旋压缩机的运行特征和应用要求。
典型型号是ZR84KC-TF5 和ZR144KC-TFD。
其余知识可从谷轮公司网站 在线产品知识里查到。
谷轮涡旋压缩机的运行原理已在谷轮公司应用工程手册4-1312里叙述了。
有几个不同于那些小容量谷轮涡旋压缩机的运行特征和设计特点在下面加以叙述。
谷轮SUMMIT压缩机虽然为空调和热泵使用设计,但在对应于A/C和H/P使用要求范围的其它应用场合也能出色地工作。
为了获得更高的电机效率和最佳的制冷效果,把吸气口设置于机壳下部,引导回流气体流经马达。
由于吸气口置于机壳较下部,油可以从此接口溢出。
在安装和拆卸期间必须保持压缩机的竖立。
这个问题在随后的‘压缩机操作’中有说明。
应用问题谷轮涡旋压缩机有许多不同于传统活塞压缩机的应用特征。
具体详述如下:压缩机操作因油可能从位于机壳下部的吸气口溢出,直到压缩机放进系统中才能拔取吸气口的胶塞。
若可能,在操作中应保持压缩机立。
应先拔排气口的胶塞,再拔吸气口的胶塞,让压缩机里的干空气压力泄出。
在此过程中要防止油雾撒在吸气管表面引起焊接困难。
镀铜钢吸气管在焊接前应清洁干净。
严禁任何物体(如起子等工具)插入吸入口超过51mm(2英寸),否则有可能损伤吸气滤网和马达。
内部压力释放阀(IPR)SUMMIT谷轮涡旋压缩机没有内部压力释放阀。
为了保证运行安全,在设备中高压开关控制设定值不得超过425psig(30kg/cm2)安全控制高压控制:由于这些压缩机不具有内部压力释放阀,在系统中高压开关设定最大值应为425psig(30kg/cm2)。
在高级保护系统中高压开关应具有手动复位的特性。
低压控制:需要低压开关是为了保护系统缺氟。
建议A/C系统低压切断设定值不要低于25psig,对于热泵系统为7psig,当吸入回路不能安装25psig或更高的低压控制时,需要安装排气温度传感器。
本文由谷轮压缩机(w w w.g u l u n.o r g)提供压缩机启动运行操作规则1、试运行前的准备11试漏:压缩机出厂时进行了干燥、检漏处理,并冲有保护气体(氮气)。
使用时建议采用工业氮气(N z)试压检漏。
用干燥空气检漏时,压缩机的吸排气阀应关闭,与系统隔离,以免影响冷冻油的稳是性。
试压检漏压力为162M p a(表压)。
1.2抽真空:检漏后,系统包括压缩机应使用真空泵抽空气,不可使用压缩机本身抽空气,真空泵要蔑时接到压缩机的高压侧和低压侧。
系统抽空气到绝对压力≤150P a(此时制冷系统所有阀件包括电磁舞均应处于开启状态),保持30分钟,压力不应变化。
注意:不要在真空下启动压缩机,不要接任何电源…即使为试验目的也是不允许的。
1.3充制冷剂:在充制冷剂或运行压缩机前先检查油面(如图5),并开通曲轴箱中电加热器。
制冷剂噩在压缩机关机状态以液态形式直接加入冷凝器或贮液器(对满液式蒸发系统,也可以加入蒸发器):在开车后如需进一步加制冷剂,可以在吸气侧(最好在蒸发器入口)以气体形式边运行边补充。
注意:当吸气侧以液态形式充制冷剂时特别要注意一下几点:131液击(湿运行)运行是十分危险的。
132曲轴箱油温一般应高于环境温度15~20度,最好大于40度。
133安全装置的设定和运行情况:时间继电器的设定;油压差继电器延时时间;高压和低压控制器的断开压力。
134开机前检查油位(液面在图5视油镜范围内)。
注意:如更换压缩机。
可能需要放掉一些油,因为系统中已存在冷冻油,如果系统中存在大量的油l i能由于前一台压缩机的故障),有产生油击(敲缸)的危险。
运转中适当的油位油过多三条竖线全g口淹没可见.应将油排放到适当的油位2、启动运行操作2 1开机前的准备工作。
2.1 1压缩机的油位应在图5视油镜的范围之内。
2.1 2贮液器的液位应在视液镜的1/2处。
213各压力表的阀应处于开启状态,自控仪表指针应调整到要求的数值。
谷轮压缩机使用指南谷轮压缩机使用指南1:简介谷轮压缩机是一种常用的压缩设备,主要用于将气体压缩为高压气体,以便在工业生产中使用。
本使用指南将详细介绍谷轮压缩机的使用方法和注意事项。
2:安全须知在使用谷轮压缩机之前,请务必遵守以下安全须知:- 在操作谷轮压缩机之前,确保已经接受相关培训并了解设备的工作原理和操作流程。
- 使用谷轮压缩机时,必须佩戴适当的个人防护设备,如护目镜、手套和安全鞋。
- 在操作过程中,应严格遵守相关安全操作规程,注意安全阀的状态,并确保压力不超过设定范围。
- 在清洁和维修设备前,务必先将谷轮压缩机与电源断开,并等待设备冷却。
3:谷轮压缩机的组成和工作原理谷轮压缩机主要由以下几个部件组成:- 谷轮:用于压缩气体。
- 凸轮:控制谷轮的运转。
- 进气阀和排气阀:调整气体的进出。
- 冷却系统:用于降低设备的温度。
谷轮压缩机的工作原理是通过谷轮的旋转来吸入气体,并将其压缩后排出。
进气阀在气体进入时打开,而排气阀则在气体压缩到一定压力后打开,释放压缩气体。
4:使用步骤4.1 准备工作- 检查设备和周围环境是否干净,无障碍物。
- 检查电源连接是否正常。
- 检查冷却系统的工作状态。
4.2 启动谷轮压缩机- 打开电源,并观察设备是否正常启动。
- 若设备正常运转,请等待一段时间,使其达到额定工作温度。
4.3 操作谷轮压缩机- 操作面板上的控制按钮和旋钮,调整进气和排气阀的开启程度,以控制气体的压缩程度。
- 当需要停止谷轮压缩机时,先调整进气阀和排气阀关闭,然后断开电源。
5:维护和保养- 定期清洁设备,去除污垢和积尘,注意不要损坏设备表面。
- 检查设备的冷却系统,保证其正常运作。
- 定期检查进气阀和排气阀的状态,并涂抹适量的润滑油。
6:附件本文档涉及以下附件:- 设备操作手册- 维修记录表- 安全操作规程- 故障排除手册7:法律名词及注释- 设备:指谷轮压缩机及其相关部件。
- 个人防护设备:用于保护操作人员安全的设备,如护目镜、手套等。
中间补气涡旋压缩机使用手册 大连三洋压缩机有限公司1. 技术背景......................................................................................32. 压缩机命名规则..........................................................................33. 系统运行流程..............................................................................44. 压缩机运行范围..........................................................................55. 配套附件清单..............................................................................71. 技术背景普通涡旋压缩机在低蒸发温度下运行时,会发生吸气比容增大、压比升高,排气温度快速升高等问题,造成压缩机性能急剧下降和制热量不足以及难以运行,为解决这一问题,开发了带有中间补气功能的涡旋压缩机。
中间补气涡旋压缩机即在压缩机压缩中间腔补充中压气体,增加排气量,降低排气温度,提升制热能力,使热泵空调器在低环境温度也能提供足够的制热能力。
同时,补气通道的开启和关闭可以做为一种容量卸载调节的辅助手段。
2. 压缩机命名规则在涡旋压缩机的设计开发、改进工作中,需要对新的压缩机型号命名。
为了规范压缩机型号命名,本公司制定了压缩机命名规则。
此规则适用于由大连三洋压缩机有限公司(DSA)涡旋工厂所设计、开发、改进的涡旋压缩机型号命名。
补气涡旋压缩机命名规则如下(补气压缩机系列代号见表1):C - SB R 120 H 38 Q1 2 3 4 5 61—— 涡旋B系列压缩机2—— 标准R22机型3—— 公称冷冻能力= 60Hz 公称冷冻能力(W)/ 1004—— 用途:高温用5—— 电制:三相B8 50Hz 380,415V / 60Hz 440,460V6—— 开发代号:补气系列表1 补气压缩机系列代号马力/HP 型号3.5 C-SBR120H38Q4 C-SBR145H38Q5 C-SBR180H38Q8 C-SCR295H38Q10 C-SCR370H38Q3.系统运行流程压缩机图1 压缩机设计系统运行流程图该设计系统的运行流程如图1所示,压缩机排出的高温、高压制冷剂气体,经冷凝器将热量传递给载热介质后变为液体,从冷凝器出来的高压制冷剂液体经储液器,通过干燥过滤器、视液镜后分为两路,主路的制冷剂液体直接进入经济器内,辅路的制冷剂液体先经过一个电磁阀,再经过膨胀阀节流降压后变为气液混合物后也进入经济器内,二者在经济器中产生热交换,辅路的制冷剂液体吸热后变为气体后被压缩机的辅助进气口吸入,主路的制冷剂放热变为过冷液体经膨胀阀节流降压后进入蒸发器。
.一般用喷水单螺杆空气压缩机ZW OILFREE使用手册复盛公司目录1.压缩机规格 (3)1-1 产品规范 (3)1-2 外观图 (7)1-3 内部配置图 (13)1-4 电器线路图 (19)1-4-1电器配置图 (19)1-4-2 线路控制与端子接线图 (24)1-5 管路系统 (26)2. 安装须知 (30)2-1 搬运 (30)2-2 安装地点 (31)2-3 管路 (34)2-4 电器接线 (36)2-5 安装完成 (38)3. 运转操作 (39)3-1 运转前检查 (39)3-2 初次运转 (40)3-3 例行运转 (43)3-4 运转说明 (44)3-5 长期停机 (44)4. 维护保养 (45)4-1 清洁前置过滤网 (45)4-2 主要零件保养 (46)4-3 进气阀调整 (59)4-4 自动补泄水系统 (63)4-5 自动换水功能 (69)4-6 马达轴承润滑 (69)4-7 保护装置 (70)4-8 定期检查维护 (72)4-9 故障排除指南 (74)4-10 ZW型-螺旋式空压机压缩原理 (77)压缩机规格1-1 产品规范ZW375A/WZW555/755WZW905-1205W1-2 外观图ZW155/225AZW375AZW375WZW555/755WZW905~1205W1-3 内部配置图ZW155/225AZW375AZW375WZW555/755WZW905~1205W1-4 电器线路图1-4-1电器配置图ZW155/225AZW375A / WZW90~120W1-4-2 线路控制与端子接线图1-5 管路系统ZW155~375AZW375WZW555/755WZW905~1205W2. 安装须知2-1 搬运2-1-1 使用堆高机 2-1-2 使用吊钩机型总重量 (Kg) ZW155A550 ZW225A640 ZW375A750 ZW375W720 ZW555W1530 ZW755W1630 ZW905W2395 ZW1005W 2445使用护板依重量(如下表)使用强度足够的吊索,并调整长度,务必使货品保持水平。
AE4-1381May 2011ZW21 to ZW61KAE and ZW30 to ZW61KSECopeland Scroll® Water Heating CompressorsTABLE OF CONTENTSSection Page Section PageIntroduction (2)ZW**KA Application (2)ZW**KS ApplicationVapour Injection - Theory of Operation (2)Heat Exchanger and Expansion Device Sizing (3)Flash Tank Application (3)Intermediate Pressure and Vapour Injection Superheat (3)Application ConsiderationsHigh Pressure Cut-Out (4)Low Pressure Cut-Out (4)Discharge Temperature Protection (4)Discharge Temperature Control (4)Discharge Mufflers (4)Oil Dilution and Compressor Cooling (4)Electrical Considerations (5)Brazing and Vapour Injection Line (5)Low Ambient Cut-Out (5)Internal Pressure Relief Valve (5)Internal Temperature Protection (5)Quiet Shutdown (5)Discharge Check Valve (5)Motor Protector (5)Accumulators (5)Screens (6)Crankcase Heat-Single Phase (6)Crankcase Heat-Three Phase (6)Pump Down Cycle (6)Minimum Run Time (6)Reversing Valves (6)Oil Type (7)System Noise & Vibration (7)Single Phase Starting Characteristics (7)PTC Start Components (7)Electrical Connections (7)Deep Vacuum Operation (7)Shell Temperature (7)Suction & Discharge Fittings (7)Three Phase Scroll Compressors (8)Brief Power Interruptions ..........................................8Assembly Line ProceduresInstalling the Compressor (8)Assembly Line Brazing Procedure (8)Pressure Testing (8)Assembly Line System Charging Procedure (8)High Potential (AC Hipot) Testing (9)Unbrazing System Components (9)Service ProceduresCopeland Scroll Functional Check (9)Compressor Replacement After Motor Burn (10)Start Up of a New or Replacement Compressor (10)FiguresBrief Product Overview (11)ZW21KAE Envelope (R-134a) (11)ZWKAE Envelope (R-407C, Dew Point) (12)ZWKA Envelope (R-22) (12)ZWKS Envelope (R-22) (13)ZWKSE Envelope (R-407C, Dew Point) (13)Heat Pump with Vapour Injection – EXV Control (14)Heat Exchanger Schematic (14)Heat Pump with Flash Tank (15)Possible Flash Tank Configuration (15)Oil Dilution Chart (16)Crankcase Heater (17)Compressor Electrical Connection (17)Scroll Tube Brazing (17)How a Scroll Works (18)IntroductionThe ZW**KA and ZW**KS Copeland Scroll®compressors are designed for use in vapour compression heat pump water heating applications. Typical model numbers include ZW30KA-PFS and ZW61KSE-TFP. This bulletin addresses the specifics of water heating in the early part and deals with the common characteristics and general application guidelines for Copeland Scroll compressors in the later sections. Operating principles of the scroll compressor are described in Figure 15 at the end of this bulletin.As the drive for energy efficiency intensifies, water heating by fossil-fueled boilers and electric elements is being displaced by vapour compression heat pumps. Emerson Climate Technologies has developed two lines of special water heater compressors to meet the requirements of this demanding application. ZW**KA compressors are designed for lighter duty applications where the ambient temperature does not fall below 0°C and where lower water temperatures can be accepted as the ambient temperature falls. ZW**KS compressors are equipped with a vapour injection cycle which allows reliable operation in cold climates with significantly enhanced heating capacity, higher efficiency, and minimal requirement to reduce water outlet temperatures. Figure 1gives a brief product overview.Water heating is characterized by long operating hours at both high load and high compression ratios. Demand for hot water is at its highest when ambients are low and when conventional heat pump capacity falls off. On the positive side, the system refrigerant charge is usually small, so the risk to the compressor from dilution and flooded starts will usually be lower than in split type air-to-air heat pumps.Water heaters must operate in a wide range of ambient temperatures, and many systems will require some method of defrost. Some systems such as Direct Heating, Top Down Heating or Single Pass Heating operate at a constant water outlet temperature with variable water flow. Others such as Recirculation Heating, Cyclic Heating or Multipass Heating use constant water flow with the water outlet and inlet temperatures both rising slowly as the storage tank heats up. Both system types need to cope with reheating a tank where the hot water has been partially used, and reheating to the setpoint temperature is required. More complex systems deliver water at relatively low temperatures for under-floor heating circuits and are switched over to sanitary water heating a few times per day to provide higher temperature water for sanitary use. In addition, some countries have specific water temperature requirements for legionella control.ZW**KA ApplicationThe application envelopes for ZW**KA compressors are shown in Figures 2 - 4.Appropriate system hardware and control logic must be employed to ensure that the compressor is always operating within the envelope. Small short-term excursions outside the envelope are acceptable at the time of defrost when the load on the compressor is low. Operation with suction superheat of 5 -10K is generally acceptable except at an evaporating tem-perature above 100C when a minimum superheat of 10K is required.ZW**KS ApplicationThe ZW**KS* vapour-injected scroll compressors differ from ZW**KA models in many important details:• Addition of vapour injection• Significantly different application envelopes• Some differences in locked rotor amps (LRA), maximum continuous current (MCC), andmaximum operating current (MOC) – seenameplatesThe application envelopes for ZW**KS compressors are shown in Figures 5 and 6.Vapour Injection – Theory of Operation Operation with vapour injection increases the capacity of the outdoor coil and in turn the capacity and efficiency of the system – especially in low ambient temperatures. A typical schematic is shown in Figure 7. A heat exchanger is added to the liquid line and is used to cool the liquid being delivered to the heating expansion device. Part of the liquid refrigerant flow is flashed through an expansion valve on the evaporator side of the heat exchanger at an intermediate pressure and used to subcool the main flow of liquid to the main expansion device. Vapour from the liquid evaporating at intermediate pressure is fed to the vapour injection port on the ZW**KS compressor. This refrigerant is injected into the mid-compression cycle of the scroll compressor and compressed to discharge pressure. Heating capacity is increased, because low temperature liquid with lower specific enthalpy supplied to the outdoor coil increases the amount of heat that can be absorbed from the ambient air. Increased heat absorbed from the ambient increases the system condensing temperature and in turn the compressor power input. The increase in power inputalso contributes to the improvement in the overall heating capacity.Vapour Injection can be turned on and off by the addition of an optional solenoid valve on the vapour injection line on systems using a thermostatic expansion valve. Alternatively, an electronic expansion valve can be used to turn vapour injection on and off and to control the vapour injection superheat. A capillary tube is not suitable for controlling vapour injection.The major advantage of the electronic expansion valve is that it can be used to optimise the performance of the system and at the same time control the discharge temperature by injecting “wet vapour” at extreme operating conditions.The configurations and schematics shown are for reference only and are not applicable to every system. Please consult with your Emerson Application Engineer.Heat Exchanger and Expansion Device Sizing Various heat exchanger designs have been used successfully as subcoolers. In general they should be sized so that the liquid outlet temperature is less than 5K above the saturated injection temperature at the customer low temperature rating point. At very high ambient temperatures, it will normally be beneficial to turn vapour injection off to limit the load on the compressor motor. Application Engineering Bulletin AE4-1327 and Emerson Climate Technologies Product Selection Software can be used to help size the subcooling heat exchanger and thermal expansion valves, but selection and proper operation must be checked during development testing. Plate type subcoolers must be installed vertically with the injection expansion device connected at the bottom through a straight tube at least 150mm long to ensure good liquid distribution. See the schematic in Figure 8. Flash Tank ApplicationA possible flash tank configuration is shown in Figure9. This particular configuration is arranged to have flow through the flash tank and expansion devices in heating, and it bypasses the tank in defrost mode. The flash tank system works by taking liquid from the condenser and metering it into a vessel through a high-to-medium pressure expansion device. Part of the liquid boils off and is directed to the compressor vapour injection port. This refrigerant is injected into the mid-compression cycle of the scroll compressor and compressed to discharge pressure. The remaining liquid is cooled, exits from the bottom of the tank at intermediate pressure, and flows to the medium-to-low pressure expansion device which feeds the outdoor coil. Low temperature liquid with lower specific enthalpy increases the capacity of the evaporator without increasing mass flow and system pressure drops.Recommended tank sizing for single compressor application in this size range is a minimum of 200 mm high by 75 mm in diameter with 3/8 in. (9.5mm) tubing connections, although it is possible to use a larger tank to combine the liquid/vapour separation and receiver functions in one vessel. A sight tube (liquid level gauge) should be added to the tank for observation of liquid levels during lab testing. See schematic diagram Figure 10 for clarification.It is important to maintain a visible liquid refrigerant level in the tank under all operating conditions. Ideally the liquid level should be maintained in the 1/3 to 2/3 full range.Under no circumstances should the level drop to empty or rise to a full tank. As the tank level rises, liquid droplets tend to be swept into the vapour line leading to “wet” vapour injection. Although this can be useful for cooling a hot compressor, the liquid quantity cannot be easily controlled. Compressor damage is possible if the tank overflows. If liquid injection is required for any reason, it can be arranged as shown in Figures 7 and 9.Since liquid leaves the tank in a saturated state, any pressure drop or temperature rise in the line to the medium-to-low pressure expansion device will lead to bubble formation. Design or selection of the medium-to-low pressure expansion device requires careful attention due to the possible presence of bubbles at the inlet and the low pressure difference available to drive the liquid into the evaporator. An electronic expansion valve is the preferred choice. Intermediate Pressure and Vapour Injection SuperheatPressure in the flash tank cannot be set and is a complex function of the compressor inlet condition and liquid condition at the inlet of the high-to-medium pressure expansion device. However, liquid level can be adjusted, which in turn will vary the amount of liquid subcooling in the condenser (water to refrigerant heat exchanger) and vary the injection pressure. Systems with low condenser subcooling will derive the biggest gains by the addition of vapour injection. Systems operating with high pressure ratios will show the largest gains when vapour injection is applied. Such systems will have higher vapour pressure and higher injectionmass flow. Intermediate pressures in flash tank and heat exchanger systems should be very similar unless the subcooling heat exchanger is undersized and there is a large temperature difference between the evaporator and the liquid sides. Vapour exiting a flash tank will be saturated and may pick up 1 - 2K superheat in the vapour line to the compressor. Vapour injection superheat cannot be adjusted on flash tank systems. Heat exchanger systems will be at their most efficient when the vapour injection superheat is maintained at approximately 5K.APPLICATION CONSIDERATIONSHigh Pressure Cut OutIf a high pressure control is used with these compressors, the recommended maximum cut out settings are listed in Figure 1. The high pressure control should have a manual reset feature for the highest level of system protection. It is not recommended to use the compressor to test the high pressure switch function during the assembly line test.Although R-407C runs with higher discharge pressure than R-22, a common setting can be used. The cutout settings for R-134a are much lower, and the switches must be selected or adjusted accordingly.Low Pressure Cut OutA low pressure cut out is an effective protection against loss of charge or partial blockage in the system. The cut out should not be set more than 3 - 5K equivalent suction pressure below the lowest operating point in the application envelope. Nuisance trips during defrost can be avoided by ignoring the switch until defrost is finished or by locating it in the line between the evaporator outlet and the reversing valve. This line will be at discharge pressure during defrost. Recommended settings are given in Figure 1. Discharge Temperature ProtectionAlthough ZW compressors have an internal bi-metal Therm-O-Disc®(TOD) on the muffler plate, external discharge temperature protection is recommended for a higher level of protection and to enable monitoring and control of vapour injection on ZW**KS* models. The protection system should shut down the compressor when the discharge line temperature reaches 125°C. In low ambient operation, the temperature difference between the scroll center and the discharge line is significantly increased, so protection at a lower discharge temperature, e.g. 120°C when the ambient is below 0°C, will enhance system safety. For the highest level of system protection, the discharge temperature control should have a manual reset feature. The discharge sensor needs to be well insulated to ensure that the line temperature is accurately read. The insulation material must not deteriorate over the expected life of the unit.Discharge Temperature ControlSome systems use an electronic expansion valve to control the vapour injection superheat and a thermistor to monitor the discharge temperature. This combination allows the system designer to inject a small quantity of liquid to keep the discharge temperature within safe limits and avoid an unnecessary trip. Liquid injection should begin at approximately 115°C and should be discontinued when the temperature falls to 105°C. Correct functioning of this system should be verified during system development. It is far preferable to use liquid injection into the vapour injection port to keep the compressor cool rather than inject liquid into the compressor suction which runs the risk of diluting the oil and washing the oil from the moving parts. If some operation mode requires liquid injection but without the added capacity associated with “wet” vapour injection, a liquid injection bypass circuit can be arranged as shown in Figures 7 and 9.Caution: Although the discharge and oil temperature are within acceptable limits, the suction and discharge pressures cannot be ignored and must also fall within the approved application envelope.Discharge MufflersDischarge mufflers are not normally required in water heaters since the refrigerant does not circulate within the occupied space.Oil Dilution and Compressor CoolingThe oil temperature diagram shown in Figure 11is commonly used to make a judgment about acceptable levels of floodback in heat pump operation. Systems operating with oil temperatures near the lower limit line are never at their most efficient. Low ambient heating capacity and efficiency will both be higher if floodback is eliminated and the system runs with 1 - 5K suction superheat. Discharge temperature can be controlled by vapour injection, “wet” vapour injection, or even liquid injection if necessary. In this situation, the oil temperature will rise well into the safe zone, and the compressor will not be at risk of failure from diluted oil. The oil circulation rate will also be reduced as crankcase foaming disappears. Special care needs to be taken at the end of defrost to ensure that the compressor oil is not unacceptably diluted. The system will resume heating very quickly and bearing loads willincrease accordingly, so proper lubrication must be ensured.Electrical ConsiderationsMotor configuration and protection are similar to those of standard Copeland Scroll compressors. In some cases, a larger motor is required in the ZW**KS* models to handle the load imposed by operating with vapour injection. Wiring and fuse sizes should be reviewed accordingly.Brazing the Vapour Injection LineThe vapour injection connection is made from copper coated steel, and the techniques used for brazing the suction and discharge fittings apply to this fitting also. Low Ambient Cut-OutA low ambient cut-out is not required to limit heat pump operation with ZW**KS compressors. Water heaters using ZW**KA compressors must not be allowed to run in low ambients since this configuration would run outside of the approved operating envelope causing overheating or excessive wear. A low ambient cut-out should be set at 0°C for ZW**KA modelsIn common with many Copeland Scroll compressors, ZW models include the features described below: Internal Pressure Relief (IPR) ValveAll ZW compressors contain an internal pressure relief valve that is located between the high side and the low side of the compressor. It is designed to open when the discharge-to-suction differential pressure exceeds 26 - 32 bar. When the valve opens, hot discharge gas is routed back into the area of the motor protector to cause a trip.Internal Temperature ProtectionThe Therm-O-Disc® or TOD is a temperature-sensitive snap disc device located on the muffler plate between the high and low pressure sides of the compressor. It is designed to open and route excessively hot discharge gas back to the motor protector. During a situation such as loss of charge, the compressor will be protected for some time while it trips the protector. However, as refrigerant leaks out, the mass flow and the amperage draw are reduced and the scrolls will start to overheat.A low pressure control is recommended for loss of charge protection in heat pumps for the highest level of system protection. A cut out setting no lower than 2.5 bar for ZW**KA* models and 0.5 bar for ZW**KS* models is recommended. The low pressure cut-out, if installed in the suction line to the compressor, can provide additional protection against an expansion device failed in the closed position, a closed liquid line or suction line service valve, or a blocked liquid line screen, filter, orifice, or TXV. All of these can starve the compressor for refrigerant and result in compressor failure. The low pressure cut-out should have a manual reset feature for the highest level of system protection. If a compressor is allowed to cycle after a fault is detected, there is a high probability that the compressor will be damaged and the system contaminated with debris from the failed compressor and decomposed oil.If current monitoring to the compressor is available, the system controller can take advantage of the compressor TOD and internal protector operation. The controller can lock out the compressor if current draw is not coincident with the contactor energizing, implying that the compressor has shut off on its internal protector. This will prevent unnecessary compressor cycling on a fault condition until corrective action can be taken.Quiet Shut downAll scrolls in this size range have a fast acting valve in the center of the fixed scroll which provides a very quiet shutdown solution. Pressure will equalize internally very rapidly and a time delay is not required for any of the ZW compressors to restart. Also refer to the section on “Brief Power Interruption”. Discharge Check ValveA low mass, disc-type check valve in the discharge fitting of the compressor prevents the high side, high pressure discharge gas from flowing rapidly back through the compressor. This check valve was not designed to be used with recycling pump down because it is not entirely leak-proof.Motor ProtectorConventional internal line break motor protection is provided. The protector opens the common connection of a single-phase motor and the center of the Y connection on three-phase motors. The three-phase protector provides primary single-phase protection. Both types of protectors react to current and motor winding temperature.AccumulatorsThe use of accumulators is very dependent on the application. The scroll’s inherent ability to handle liquid refrigerant during occasional operating flood back situations often makes the use of an accumulator unnecessary in many designs. If flood back is excessive, it can dilute the oil to such an extent thatbearings are inadequately lubricated, and wear will occur. In such a case, an accumulator must be used to reduce flood back to a safe level that the compressor can handle.In water heaters, floodback is likely to occur when the outdoor coil frosts. The defrost test must be done at an outdoor ambient temperature of around 0°C in a high humidity environment. Liquid floodback must be monitored during reversing valve operation, especially when coming out of defrost. Excessive floodback occurs when the sump temperature drops below the safe operation line shown in Figure 11 for more than 10 seconds.If an accumulator is required, the oil return orifice should be 1 - 1.5mm in diameter depending on compressor size and compressor flood back results. Final oil return hole size should be determined through testing. ScreensScreens with a mesh size finer than 30 x 30 (0.6mm openings) should not be used anywhere in the system with these compressors. Field experience has shown that finer mesh screens used to protect thermal expansion valves, capillary tubes, or accumulators can become temporarily or permanently plugged with normal system debris and block the flow of either oil or refrigerant to the compressor. Such blockage can result in compressor failure.Crankcase Heater - Single PhaseCrankcase heaters are not required on single phase compressors when the system charge is not over 120% of the limit shown in Figure 1. A crankcase heater is required for systems containing more than 120% of the compressor refrigerant charge limit listed in Figure 1. This includes long line length systems where the extra charge will increase the standard factory charge above the 120% limit.Experience has shown that compressors may fill with liquid refrigerant under certain circumstances and system configurations, notably after longer off cycles when the compressor has cooled. This may cause excessive start-up clearing noise, or the compressor may lock up and trip on the protector several times before starting. The addition of a crankcase heater will reduce customer noise and light dimming complaints since the compressor will no longer have to clear out liquid during startup. Figure 12lists the crankcase heaters recommended for the various models and voltages.Crankcase Heat – Three-PhaseA crankcase heater is required for three-phase compressors when the system charge exceeds the compressor charge limit listed in Figure 1and an accumulator cannot be piped to provide free liquid drainage during the off cycle.Pump Down CycleA pump down cycle for control of refrigerant migration is not recommended for scroll compressors of this size. If a pump down cycle is used, a separate external check valve must be added.The scroll discharge check valve is designed to stop extended reverse rotation and prevent high-pressure gas from leaking rapidly into the low side after shut off. The check valve will in some cases leak more than reciprocating compressor discharge reeds, normally used with pump down, causing the scroll compressor to cycle more frequently. Repeated short-cycling of this nature can result in a low oil situation and consequent damage to the compressor. The low-pressure control differential has to be reviewed since a relatively large volume of gas will re-expand from the high side of the compressor into the low side on shut down. Minimum Run TimeThere is no set answer to how often scroll compressors can be started and stopped in an hour, since it is highly dependent on system configuration. Other than the considerations in the section on Brief Power Interruptions, there is no minimum off time. This is because scroll compressors start unloaded, even if the system has unbalanced pressures. The most critical consideration is the minimum run time required to return oil to the compressor after startup.Since water heaters are generally of compact construction, oil return and short cycling issues are rare. Oil return should not be a problem unless the accumulator oil hole is blocked.Reversing ValvesSince Copeland Scroll compressors have very high volumetric efficiency, their displacements are lower than those of comparable capacity reciprocating compressors. As a result, Emerson recommends that the capacity rating on reversing valves be no more than 2 times the nominal capacity of the compressor with which it will be used in order to ensure proper operation of the reversing valve under all operating conditions.The reversing valve solenoid should be wired so that the valve does not reverse when the system isshut off by the operating thermostat in the heating or cooling mode. If the valve is allowed to reverse at system shutoff, suction and discharge pressures are reversed to the compressor. This results in pressures equalizing through the compressor which can cause the compressor to slowly rotate until the pressures equalize. This condition does not affect compressor durability but can cause unexpected sound after the compressor is turned off.Oil TypeThe ZW**K* compressors are originally charged with mineral oil. A standard 3GS oil may be used if the addition of oil in the field is required. See the compressor nameplate for original oil charge. A complete recharge should be ~100 ml less than the nameplate value.ZW**K*E are charged with POE oil. Copeland 3MAF or Ultra 22 CC should be used if additional oil is needed in the field. Mobil Arctic EAL22CC, Emkarate RL22, Emkarate 32CF and Emkarate 3MAF are acceptable alternatives. POE oil is highly hygroscopic, and the oil should not be exposed to the atmosphere except for the very short period required to make the brazing connections to the compressor.System Noise and VibrationCopeland Scroll compressors inherently have low sound and vibration characteristics, but the characteristics differ in some respects from those of reciprocating or rotary compressors. The scroll compressor makes both a rocking and a torsional motion, and enough flexibility must be provided to prevent vibration transmission into any lines attached to the unit. This is usually achieved by having tubing runs at least 30cm long parallel to the compressor crankshaft and close to the shell. ZW compressors are delivered with rubber grommets to reduce vibration transmission to the system baseplate.Single Phase Starting CharacteristicsStart assist devices are usually not required, even if a system utilizes non-bleed expansion valves. Due to the inherent design of the Copeland Scroll, the internal compression components always start unloaded even if system pressures are not balanced. In addition, since internal compressor pressures are always balanced at startup, low voltage starting characteristics are excellent for Copeland Scroll compressors. Starting current on any compressor may result in a significant “sag” in voltage where a poor power supply is encountered. The low starting voltage reduces the starting torque of the compressor and subsequently increases the start time. This could cause light dimming or a buzzing noise where wire is pulled through conduit. If required, a start capacitor and potential relay can be added to the electrical circuit. This will substantially reduce start time and consequently the magnitude and duration of both light dimming and conduit buzzing.PTC Start ComponentsFor less severe voltage drops or as a start boost, solid state Positive Temperature Coefficient devices rated from 10 to 25 ohms may be used to facilitate starting for any of these compressors.Electrical ConnectionThe orientation of the electrical connections on the Copeland Scroll compressors is shown in Figure 13 and is also shown on the wiring diagram on the top of the terminal box cover.Deep Vacuum OperationScrolls incorporate internal low vacuum protection and will stop pumping (unload) when the pressure ratio exceeds approximately 10:1. There is an audible increase in sound when the scrolls start unloading. This feature does not prevent overheating and destruction of the scrolls, but it does protect the power terminals from internal arcing.Copeland Scroll compressors(as with any refrigerant compressor) should never be used to evacuate a refrigeration or air conditioning system. The scroll compressor can be used to pump down refrigerant in a unit as long as the pressures remain within the operating envelope. Prolonged operation at low suction pressures will result in overheating of the scrolls and permanent damage to the scroll tips, drive bearings and internal seal. (See AE24-1105 for proper system evacuation procedures.)Shell TemperatureCertain types of system failures, such as condenser or evaporator blockage or loss of charge, may cause the top shell and discharge line to briefly but repeatedly reach temperatures above 175ºC as the compressor cycles on its internal protection devices. Care must be taken to ensure that wiring or other materials, which could be damaged by these temperatures, do not come in contact with these potentially hot areas. Suction and Discharge FittingsCopeland Scroll compressors have copper plated steel suction and discharge fittings. These fittings are far more rugged and less prone to leaks than。