Brooks Polycold MaxCool Series - Electrical Protection Requirements - Maxcool 4000 H and 2500 L; Electrical Specification Notes

Polycold Cryochiller Specifications and Site Preparation
Installation and Operation Manual Electrical
Brooks Automation
214072 Revision B
3-5
Electrical Protection Requirements - MaxCool 4000H and 2500L
All voltages are nominal +10%/-10%, unless otherwise stated.
Note 1: 35Amp breaker is allowable for 380-3-50 setting when nominal voltage is 380V +10% / -5%.
Note 2: 45Amp breaker is required for 380-3-50 setting when nominal voltage is 380V +10% / -10%.
Electrical Specification Notes
• The Cryochiller is shipped with transformer tap settings for the voltage specified on the system
label. If voltage is outside of the specified range, the transformer taps must be changed.
• 24 volt transformers on systems capable of 230 to 480 Volt power input may be configured in
the field to the actual voltage. Refer to Change Transformer Tap Settings on page 4-16.
• RLA = Rated Load Amps is the current drawn by the compressor at rated load. It may also be
referred to as the maximum full load amps.
• A Bussman FRS-R dual element, current limiting fuse or equivalent is recommended to protect
the Polycold Cryochiller power circuit.
• Actual protection must comply with local codes.
• “Worst Case low Volts” refers to the lowest amount of voltage available. Power fluctuates by
10%, so the lowest voltage amount would be 90% of the nominal voltage.
• MCC = Maximum Continuous Current of the compressor motor.
• LRA = Locked Rotor Amps. This refers to the current that the compressor motor uses when the
compressor is not able to rotate because the rotors are locked.
• Gould TRS, Littelfuse FLSR, MCA, minimum circuit ampacity, should be at least 125% RLA.
This value is to assist the site electrician in determining the dimensions of the electrical system.
• Compressors are provided with over current and over temperature protection which comply
with UL and NEC definitions of inherent thermal protection.
kVA = (Test Volts) X (RLA) X (1.732/1000)
kW = (kVA) X Power Factor (Power Factor is 90% in this case.)
Table 3-5: MaxCool 4000H and 2500L Cryochiller Electrical Protection Requirements
Transformer
Tap Setting
and ID Label
RLA Amps MCC Amps LRA Amps
Fuse Size
Amps
Power Input
kVA
200-3-50/60 55.4 75 160 80 19.2
230-3-50/60 48.3 75 160 80 19.2
380-3-50 27.2 39 80
35 (see Note 1)
45 (see Note 2)
17.9
400-3-50 25.8 39 80 35 17.9
460-3-50/60 25.4 39 80 35 20.2
480-3-60 21.5 39 80 35 17.9
575-3-60 17.9 31.2 64 35 17.8