10-02-2011 07:14 PM
I need some assistance on G3516C engine generators. We are starting up our 1st of 3 G3516C generator sets and having trouble with the kw load signal from the Cat supplied watt transducer (324-9125). There seems to be a problem with the PT ration compared to the Cat supplied watt transducer. The gensets are 3300V, 50hz, which has a site PT ration of 3300:110 to the control panel (off-skid 3rd party panel), but for now we are shop testing with 3300V:120 PTs. If calculated out we cannot achieve the desired 0-4.0V required to the ECM of 100% load or 4.8V on 110% load with this transducer. With the shop PTs and a 400:5 CT ration I come up with a required 7.067 transducer output @ full rated genset power (1555kw) for these units.
Are we doing something wrong in relationship to applied load or calculations? Or is this transducer wrong for our application? (This the Caterpillar supplied watt transducer that came with these gensets). All connection have been check. Is the instrument power input on TB#12 & #9 required? Purpose? I have sometimes seen this as an optional connection.
The engine will not accept full load applied, ADEM goes into fault. The watt transducer does not seem to operate correctly as to load signal to the EMC/ADEM. We have disconnected the feed to the ADEM from the transducer and added in a pot to simulated the applied load. This to indicate load signal to ADEM. Seems to do the job for test purposes, but we need to locate the disconnect in the system.
Any assistance out there would be appreciated and welcomed. I'd like to learn as much as I can on the G3516C. Thanks.
10-04-2011 01:15 PM
I'm not sure if I fully understand the rootcause of your problem. Have you thoroughly read the Application and Installation Guide, Gas Control & Ignition Systems? Cat media number is
LEBW4982-01. There are several pages, beginning on page 20, that explore kW transducer sizing and adjustment for G3500C gensets. You should be able to get a copy electronically from your local Caterpillar Dealer.
I hope this helps.
10-04-2011 04:05 PM
Thanks Nick for replying. Yes, we have the A&I guides and Initial start up REHS1438-09. I think we found the root of the problem. Either we change our CT ratio or resize the watt transducer. Swapping out the CTs is not an option to our customer. They are in there switchgear and the remote panel is too far away for them to be installed at the generator. So I have to look at a different WT.