Download Generator Start/Stop Control Unit

P and S Automation Limited.
Project:
Start/Stop Control Unit for No. 1 Diesel Generator
Contract: 2389P
2.2 Operation and Technical Description
Refer to P&S drawing no’s:
2389-E-0127 (External Connections)
2389-E-0129 (Control Panel Items)
Additional Documentation for the General Operation of the HMI Panel:
Auto Maskin DC305 User’s Manual
Auto Maskin DC305 Installation Manual
24 VDC is applied to the control panel via terminal 1 and 6. In turn, the 24 VDC for the Oil Mist
Detector and the governor motor is supplied from the panel, via MCB’s MCB3 and MCB2
respectively.
An additional MCB4 is used to isolate the power to the start and stop solenoids.
In the event of power failure, RL13 will operate and provide an alarm out.
The following input channels are used to provide an emergency shutdown for the engine, and
are all wire-break monitored:
Oil Mist Detector High
Charge Air Temperature High
CW Temperature High
L.O. Pressure Low
Emergency Shutdown Pushbutton - Remote
Emergency Shutdown Pushbutton – Panel
All of the above are normally-open type contacts, i.e. open when the engine is running
normally, and have a 10k ohm resistor connected across the transducer terminals, at the
transducer.
(Overspeed is also a shutdown signal, but is generated internally).
Wire-break monitoring is also provided fir the emergency stop solenoid valve V303, using the
WB1 module. Current is sensed through the coil by measuring the volt drop across a (relatively
high value) series resistor and is fed to an input channel on the WB1.
Because the coil resistance is much lower than the resistor value, the voltage generated is
small (approx 1.9V), but if the coil goes open-circuit, the voltage will rise up to the resistor
supply voltage and cause the WB1 module to trip, and operate RL4, which in turn sets off a
wire-break alarm. This will also be indicated on the HMI.
Unit 47-49 Cutlers Road, South
Woodham Ferrers, Essex CM3 5WA
Tel: 01245 322777
Fax: 01245 322776
Email:
[email protected]
Website:
www.PandSautomation.com
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