Johnson Controls SABROE Unisab III Control, Engineering Manual

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Engineering manual - UniSAB III 1.10.8
306/346
001930 en 2021.06
Troubleshooting
Communication
LAN: 100 (yellow), 10 (yellow), link (green). The green link LED is on when the LAN network is con-
nected. The two yellow LEDs indicate if it is a 10/100 Mbit connection.
RS485: TxD 2 (red), Tx2 EN (yellow), RxD 2 (green), TxD 1 (red), Tx1 EN (yellow), RxD 1 (green) Profi-
bus: RxD (green), TxD (red), RTS (yellow)
SD card busy , 1 (Red)
Light in diode = SD card is busy.
Processor status , 1 (Green).
Flashing diode = Processor is active. The green light diode must flash irregularly whenever UniSAB III is
electrified. A constant light or no light is a sign of malfunctioning.
Processor reset , 1 (Red) Light in diode = Processor is resetting. The red light diode must usually be off.
It is only on for brief moments in case the CPU tries to restart the program. This may only happen while
UniSAB III is switched on.
Power on , 1 (Green)
Light in diode = Power is on.
9.1.3 Digital inputs
If a digital input is disconnected, the specific input will never become active. If the digital input is short cir-
cuit to ground the status of the specific input will switch to active.
9.1.4 Analogue inputs
If any of the analogue inputs (PT100 sensors, pressure or position transmitters) fail it will usually cause
UniSAB III to shutdown the compressor. UniSAB III will react differently depending on the failure but the
following description can be used to evaluate the error.
PT100 inputs
If the sensor is disconnected, UniSAB III will show a temperature of 200 ° C and the compressor will usu-
ally shut down on high temperature.
If the sensor is short circuit the temperature will show -200 ° C and the compressor will usually shut down
on low temperature.
Pressure inputs (4-20 mA)
If the transmitter is disconnected, UniSAB III will show a pressure of -2 to -4 bar and the compressor will
usually shut down on low pressure. If the transmitter is short circuit the pressure will show 12/33/77 bar
depending on the pressure ratio for the specific transmitter and the compressor will usually shut down
on high pressure.
The pressure transmitters are supplied by 24 VDC from UniSAB III. If the power supply is short circuit to
ground the pressure will show -2 to -4 bar and the compressor will usually shut down on low pressure.
The internal safety circuit will shut down if the power supply for the specific transmitter in the event of
short circuit to ground and UniSAB III will not be damaged. When the error has been corrected, UniSAB
III will operate normally.
Capacity and Vi slide position inputs (4-20 mA)
If the transmitter is disconnected, UniSAB III will show a position of approximately -24%. The exact read-
ing depends on the software calibration of the specific input in UniSAB III. If the compressor is running in
Auto mode it will show a capacity error alarm or shut down on Vi position error or after operating for a
while. If the compressor is running in Remote mode it will shut down on capacity error, Vi position error
or after operating for a while.