Daikin JEHBSCU0200M1 Technical Manual page 29

9.14.3 Low pressure safety (Auto reset)
The low pressure safety switch protects the compressor against deep vacuum operation, a potential cause of failure
due to internal arcing and also operation outside the compressor limits.
The low pressure safety cut out should never be set below the settings as shown in the following table. For
systems without pump-down the LP switch signal contact shall be used to energize a low pressure safety alarm.
The low pressure cut out pressure is the setting of cut in minus the differential.
There must be no more than 12 compressor starts per hour. A higher number of
starts reduce the service life of the compressor. If necessary, use an anti-short-cycle
timer in the control circuit. It is recommended minimum 2 minutes run in time and 3
minutes idle time for each start and stop of the compressor. The compressor may
run in shorter interval during pump down cycle.
9.14.4 XGE Fan Speed Controller
Model JEHSCU0750CL3 and JEHSCU0951CL3 EVI are mounted with fan speed controller which used to
regulate the bottom fan motor. The fan speed controller is factory set to 19 bar for operation with R4*** series
refrigerant to ensure compressor always operates within envelope at all declared working condition. If operate
with R134a, the fan speed controller setting need to be change to 13bar. The XGE controls are set to stop fan at
Pmin.
9.14.5 Discharge Thermostat
Model JEHSCU0750CL3 and JEHSCU0951CL3 EVI are mounted with discharge thermostat (cut out = 125⁰C,
cut in = 90⁰C) to protect the compressor. For other unit models, it is recommended to install the discharge
thermostat if operating in extreme condition (low evaporating and high ambient temperature).
9.14.6 For EVI unit only
Controller EXD-HP1
The controller EXD-HP1 used in the Series 4 EVI unit operates as an economizer control. The setting of controller
is preset by the factory and is password protected. Users are not allowed to change any settings in the controller.
T-CU01-MAR21-3
Important Note
Clockwise: Increase pressure set point
Anticlockwise: Decrease pressure set
point
0
360 = 1 turn
Approx. 1.5 barG
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