Table of Contents
Advertisement
Control System
4.1. List of Main Control Function
Water temp.
Automatic water temperature control
control
1. Starting control
2. Time Guard
Compressor
3. Sequential starting control
4. Rotation control
Current limit control
Reverse protection control
Restart function from momentary power failure
Automatic restart function from power failure <option>
Operation error/ wrong setting prevention control
Forced load control
Second water temperature setting
pag. 50
SMGB0003 rev.0-01/2007
Item
Contents
Outlet water temperature of water side heat exchanger
−
is detected by thermistor and the position of
compressor slide valve is controlled continuously.
The range of capacity control: 100~15%, Stop (all
−
models)
models)
∆ control (5 seconds), Starting unload control (30
−
sec before capacity control).
sec before capacity control).
Prevention of excessive compressor re-starts (3
−
minutes)
minutes)
Prevention of compressors' simultaneous start (1
−
minute delay) (Unit with more than 1 cycle)
minute delay) (Unit with more than 1 cycle)
Balance of each compressor running hours (more than
−
1 cycle)
1 cycle)
When unit current reaches to the setting value, power
−
supply capacity load is reduced. Therefore, unload
operation is performed forcedly for some minutes.
operation is performed forcedly for some minutes.
3 phase status is detected to avoid the operation in
−
reverse phase or open phase (before starting and
during running of unit).
during running of unit).
In case of momentary power failure (13mm seconds ≤
−
time ≤ 2 seconds, and under –20% of power voltage),
unit is stopped, and then is restarted when the voltage
is back.
In case of power failure of over 2 seconds, the units
−
are restarted after power supply is back.
In case of long-term power failure, the units are
−
restarted when oil heater has electricity for a certain
period after the power supply is back.
The units are not started automatically if power failure
−
happens during stop.
It is an optional setting by Dip Switch (DSW1 pin2).
It is an optional setting by Dip Switch (DSW1 pin2).
−
Alarm is output for such operation errors that
−
changeover from remote to local or from cooling to
heating and wrong setting.
In case that operation order is input by remote
−
controller when local operation is selected, alarm is
output as safety.
output as safety.
Forced capacity operation (forced Thermo OFF, forced
−
capacity control) is performed by external signal
attending to special needs of load.
Control is performed externally by a no-voltage contact
−
for each compressor.
It is possible to adjust 2 setting temperatures.
−
1st temperature is set by rotary switch, and 2nd
−
temperature is set by key operation on the 7 segment.
According to the usage state of loading side, setting
−
temperature can be switched by external signal (no-
voltage contact input).
voltage contact input).
Hide quick links:
Advertisement
Chapters
Table of Contents
Troubleshooting
