Engine Speed Control (WW Governor)
Throttle and DMR circuit - This circuit starts from wire no. 50 which energizes when MB2 is kept ON. Supply of wire no. 50 goes to wire no.16D - 16A when MCB1 & 2 kept ON. Supply of wire no.16A goes to 16 through MH Idle & MH in Motoring position of both control stands. When wire no.16 gets energize, DMR coil gets +ve supply.
DMR coil gets -ve supply through NCI of PCS2, PCS1, PR3 and DMR will picks up. Due to which DMR self interlocks (16A-16F-16) gets closed. These interlock maintains +ve supply of DMR coil even after opening TH Notch. As we keep ECS on RUN ERR will get supply from wire no.16 through GFOLR NCI, ECS (RUN), GR1 NCI, Stop Button NCI, and LWS NCI and ERR picks up. Due to which NOI of ERR gets close on the branch of A, B, C, D solenoids.
Supply of wire no.16 goes to wire no.7A through 7B when MUSD1 and MUSD2 of respective control stand are in run position. On opening MH notch, its interlocks close on the branches of A, B, C, D solenoids. A, B, C, D solenoids coil get energize by wire no. 15A - 4, wire no. 12A - 4, wire no. 7C - 4, wire no. 3A - 4 respectively. As Solenoid picks up Engine speed increases as per throttle notches.
Engine speed chart
Engine speed control (GE/EH) - To increase the engine speed, balance current (475 mA) of speed coil is to be decreased and vice-versa to reduce speed according to the Notch position. ESR1, 2, 3, and 4 energizes or de energizes in combination according to the Notch position accordingly its NCI open or close in governor speed coil circuit.
Throttle and DMR circuit - This circuit starts from wire no. 50 which energizes when MB2 is kept ON. Supply of wire no. 50 goes to wire no.16D - 16A when MCB1 & 2 kept ON. Supply of wire no.16A goes to 16 through MH Idle & MH in Motoring position of both control stands. When wire no.16 gets energize, DMR coil gets +ve supply.
DMR coil gets -ve supply through NCI of PCS2, PCS1, PR3 and DMR will picks up. Due to which DMR self interlocks (16A-16F-16) gets closed. These interlock maintains +ve supply of DMR coil even after opening TH Notch. Supply of wire no.16 goes to wire no.7A through 7B when MUSD1 and MUSD2 of respective control stand are in run position. On opening MH notch, its interlocks close on the branches of ESR1, 2, 3, 4 coil get energize by wire no. 15 - 4, wire no. 12 - 4, wire no. 7 - 4, wire no. 16 - 4 respectively. As ESR picks up according to notch position then resistance of various values get connected in series of Governor Speed coil. Due to which current of speed coil will decrease and engine speed will increase. But when the speed coil get balance current 475 mA than engine speed will be maintained constant as per notch position. In vice-versa when notches reduced then current of speed coil will be increased due to which engine speed will decrease.
Precautions after wedging ERR:-
1. Keep attention on water level.
2. Bring MH to Idle when GR1/GFOLR operates.
3. Use MUSD for shut down the engine.
4. Engine not comes to Idle by ECS (I)
Note:
1. If MUSD wire is uncouple / loose engine speed will not increase upto 4th notch, on opening the 5th notch engine will shut down. At this time check its wire connection.
2. If MH interlock is defective, change the control stand and work further.
