54 motor stalling manual turning, check if the compressor is stuck
General screening principles:
Confirm that the power supply voltage is within the allowable range and the control transformer gear is correct.
Check if all plugs and wiring terminals are securely fastened.
The temperature of the control cabinet shall not exceed 55 ℃.
The length of the remote control circuit should not exceed 20 meters, otherwise intermediate relays need to be used.
Be sure to tighten all connecting screws after each repair.
Basic Load Sequence (BLS) Function and Settings
BLS is an optional feature (FS and SR versions) of DELCOS 3100, used for master-slave control. The main compressor (K1) controls the loading/unloading of up to 4 slave machines (K2~K5) through the relay module (A06), and automatically rotates the basic load machines according to the operating hours.
5.1 BLS Menu Key Parameters
Suggestion for parameter meaning setting
Operation ON/OFF/TIMER enables BLS or timed activation
CUT-OUT POINT/TARGET PRESSURE Pressure band upper limit/set point pressure band width should not be less than 0.3 bar
CHANGEOVER TIME rotation interval (1-999h or 300s test) is set based on the balanced operation of each compressor
Number of slave machines participating in rotation for QUANT.SLAVES: 1-4
Quantity of spare machines (not participating in rotation) 0~(4- number of slave machines)
VOL.COMP2... 5 (RS/SR) rated flow rate (m ³/min) of each slave input according to the nameplate
SWITCH OFF DELAY peak machine cut-off delay recommended 30 seconds
Load NET IN: Charge the network within a limited time to avoid multiple machines starting simultaneously on Monday mornings
The accurate value of the total volume (m ³) of the NET VOLUME (RS/SR) pipeline network affects control stability
5.2 BLS Status Display
Example: The meaning of "123h K1 K3 k4 r2 r5" is:
123h: Remaining hours until next rotation
K1 (uppercase K): Current base load machine
K3, k4 (lowercase k): Medium load, peak load machine
R2, r5 (lowercase r): Backup machine
The faulty machine displays as' k1 'and moves to the end, alternating every second.
5.3 Common BLS Malfunctions
Warning MS-BUS: A06: Relay module failure, slave cannot load. Check the module power supply and fuses.
BLS not working: main station power outage, pressure sensor B1 malfunction, module A06 failure. After confirmation, BLS can be forcibly enabled through external contacts (input E07.4).
Inaccurate flow calculation: Check if VOL.COMP2... 5 is entered correctly and confirm that the slave returns a 'run' signal (otherwise BLS will incorrectly calculate the total flow).
Maintenance and troubleshooting of water circuit
The automatic water level adjustment and regular water replacement of the pressure tank of the water-cooled compressor are managed by the controller.
6.1 Principle of automatic water level regulation
High water level: Delay opening the drainage solenoid valve (y9) until the water level is normal. If the timeout is not completed, report FAILT DRAINAGE 5.
Low water level: Only open the water replenishment solenoid valve (y8) during loading and operation. If the timeout is not compensated to normal, report Warning Supply 5.
When the motor stops, the drain stop valve (Y10) is closed to prevent water from flowing back into the compressor.
6.2 Water exchange process
After the Change Cycle is reached, the following sequence should be executed:
Open the drain valve to the lower limit.
Open the water replenishment valve to the upper limit position.
Drain again to the normal water level and reset the cycle timer.
If the machine is unloaded or stopped during the water change period, the process will pause and continue after loading.
6.3 Troubleshooting of Water Circuit Malfunctions
Possible causes and measures of the malfunction
The simultaneous closure of two liquid level switches and inspection of the switches and wiring may be due to mechanical jamming
Warning Supply 2/Fault Supply 2 Water replenishment timeout check for inlet pressure, water treatment unit tank, water replenishment solenoid valve, and control transformer
Check if the drain solenoid valve and pipeline are blocked during the drainage timeout of FAULT DRAINAGE 1/4, and increase the DRAINAGE MAX value appropriately
Frequent water changes fail due to insufficient water supply in the water treatment unit, resulting in an increase in the water change cycle (such as 48 hours or longer)

Operation mode and remote control
7.1 Automatic mode vs. continuous mode
Automatic Operation: The most economical mode, with on-demand shutdown and standby.
Continuation Operation: To prevent frequent start stop situations, do not shut down after unloading and only run without load.
7.2 Speed Control (RS Version)
SPEED REGULATION ON: Normal speed regulation, PI control maintains target pressure.
SPEED REGULATION OFF: Fixed maximum speed, used for testing or bypassing.
Bypass operation: If the frequency converter fails, it can be switched to the star delta bypass (option). Shutdown is required first, switch the menu to BYPASS Operation, confirm that the bypass is ready, and restart.
7.3 Remote start stop and pressure switching