Emerson ZB66KC/E, ZB50KC/E, ZB58KC/E, ZB76KC/E, ZB88KC/E Application Engineering Bulletin

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Application Engineering
Application Engineering
BULLETIN
BULLETIN
AE-1318 R1
AE4-1318 R1 June
APPLICATION GUIDELINES FOR ZB*KC/ZB*KCE COPELAND SCROLL
®
Introduction
The Copeland Scroll compressor product offering has expanded to include higher horsepower models. These new models include 7-15 Hp and produce between 50,000 Btu/H and 114,000 Btu/H at 20/120°F using 60 Hz electrical power. This bulletin covers the application parameters recommended for operating these compressors properly.
Nomenclature
The ZB*KC/ZB*KCE refrigeration scroll model number includes two digits that indicate the amount of cooling capacity in thousands of Btu/H at the 60 Hz ARI rating point (20/120°F) with R404A in the third and fourth location. (e.g. ZB92KC produces approximately 92,000 Btu/H). For actual compressor performance information please visit Emerson Climate Technologies Online Product Information at www.emersonclimate.com
®
ZB*KC/ZB*KCE refrigeration
ZB*KCE (excluding ZB95KCE & ZB114KCE)
Application Envelope for R404A/R507 MT
Figure 1A
Applications 7-15Hp
2008
Operating Envelope
The Copeland Scroll refrigeration models can be used with a variety of refrigerants. Table 1 shows these selection options.
The operating envelopes are depicted in Figures 1A, 1B, 1C, 1D, 1E and 1F.
TABLE 1
Model Refrigerant Lubricant
ZB50KC/E R22/407/R404A/507/134a MO/POE
ZB58KC/E R22/407/R404A/507/134a MO/POE
ZB66KC/E R22/407/R404A/507/134a MO/POE
ZB76KC/E R22/407/R404A/507/134a MO/POE
ZB88KC/E R22 MO/POE
ZB95KC/E R22/R404A/507/134a MO/POE
ZB114KC/E R22/R404A/507/134a MO/POE
ZB56KC/E R22/R404A/507/134a MO/POE
ZB68KC/E R22/R404A/507/134a MO/POE
ZB75KC/E R22/R404A/507/134a MO/POE
ZB92KC/E R22/R404A/507/134a MO/POE
ZB11MC/E R22/R404A/507/134a MO/POE
Figure 1B
ZB95KCE & ZB114KCE Application Envelope for
R404A/R507 MT Applications 7-15Hp
20 F SH
© 2008 Emerson Climate Technologies Printed in the U.S.A.
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AE-1318 R1
Application Engineering
BULLETIN
Figure 1C
ZB95KCE & ZB114KCE Application Envelope for
R404A/R507 HT Applications 7-15Hp
20 F SH
Figure 1D
ZB*KC (excluding ZB95KC & ZB114KC)
Application Envelope for R22 HT Applications
7-15Hp
,
20 F Min. SH
Figure 1F
ZB*KCE Application Envelope for R134A HT
Applications 7-15Hp
260° F DLT Limit, 20° F Superheat
Evaporating Temperature
Voltage / Frequency Restrictions
Due to inadequate cooling from refrigerant fl ow through the compressor, the following 50 Hz applications are not approved:
ZB95KC / ZB95KCE / ZB114KC / ZB114KCE-TWD 420 V 50 Hz
Figure 1E
ZB95KC & ZB114KC Application Envelope for R22
HT Applications 7-15Hp
20 F SH
ZB95KC / ZB95KCE / ZB114KC / ZB114KCE-TW5 200-220 V 50 Hz
Compressor Lubrication
The compressors can be used with different lubricants depending upon the refrigerant used. See Form 93-11 for a complete list of all Emerson approved lubricants.
Accumulators
Due to the inherent ability of scroll compressors to handle liquid refrigerant in fl ooded start and defrost cycle operation conditions, accumulators may not be required. An accumulator is required on single compressor systems when the charge limitations exceed those values listed in Table 2. On systems with defrost schemes or transient operations that allow prolonged uncontrolled liquid return to the compressor, an accumulator is required unless a
TABLE 2
CHARGE LIMITS
Model Family Charge Limits
ZB50, 58, 66, 76, 88, 95, 114 KC/E 16 lbs
ZB56,68,75,92KC/E & ZB11MC/E 17 lbs
© 2008 Emerson Climate Technologies Printed in the U.S.A.
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AE-1318 R1
Application Engineering
BULLETIN
suction header of suffi cient volume to prevent liquid migration to the compressors is used. Excessive liquid fl oodback or repeated fl ooded starts will dilute the oil in the compressor causing inadequate lubrication and bearing wear. Proper system design will minimize liquid fl oodback, thereby ensuring maximum compressor life.
If an accumulator must be used, an oil return orifi ce size in the range of 0.040 - 0.075 inches (1 - 1.9 mm) is recommended. A large-area protective screen no fi ner than 30 x 30 mesh (0.6 mm openings) is required to protect this small orifi ce from plugging with system debris. Tests have shown that a small screen with a fi ne mesh can easily become plugged causing oil starvation to the compressor bearings.
Screens
The use of screens fi ner than 30 x 30 mesh (0.6 mm openings) anywhere in the system is not recommended. Field experience has shown that fi ner 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 fl ow of either oil or refrigerant to the compressor. Such blockage can result in compressor failure.
Crankcase Heater
Crankcase heaters are required on systems when the system charge exceeds the recommended charge limit. See Table 2.
The listed crankcase heaters (Table 3) are intended for use only when there is limited access. The heaters are not equipped for use with electrical conduit. Where applicable, electric safety codes require heater lead protection, a crankcase heater terminal box should be used. Recommended crankcase heater terminal cover and box numbers are listed in Table 3A. If there are any questions concerning the application, contact the Emerson Climate Technologies Application Engineering department.
Advanced Scroll Temperature Protection (ASTP)
After extensive research and trials Emerson Climate Technologies found a way to install a Therm-O­Disc® temperature sensitive snap disc in the ZB50, ZB58, ZB66, ZB76, ZB95, ZB88 and ZB114 scroll compressors. This acts to protect the compressor from
TABLE 3
CRANKCASE HEATERS
Model Part No. Volts Watts Leads
ZB50, ZB58,
ZB66, ZB76 ZB88, ZB95
ZB114
Select by voltage and lead length
ZB56 ZB68 ZB75 ZB92
ZB11M
Model Number Kit Number
ZB50, ZB58, ZB66 ZB76, ZB88, ZB95, ZB114
ZB56, ZB68, ZB75 ZB92, ZB11M
Select by voltage
90
018-0067-00 018-0067-01 018-0067-02 018-0067-03
018-0077-00 018-0077-01 018-0077-02 018-0077-03 018-0077-04 018-0077-05 018-0077-06
TABLE 3A
CONDUIT READY HEATER BOX KITS
120 240 480 575
240 120 480 575 240 480 575
998-7029-00
998-7015-00
90 90 90
70 70 70 70 70 70 70
48" 48" 48" 48"
26" 26" 26" 26" 34" 34" 34"
Figure 2
© 2008 Emerson Climate Technologies Printed in the U.S.A.
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