ATS for Commins 250kVA Generator

Use the telephone to talk to these people.

Most stand-by generator systems have a "cool down" cycle that lasts 5 to 15 minutes or so. This allows the generator to run in the event there was a very short outage. It is intended to allow the generator to run in those instances so it doesn't start and then immediately shut down. This is adjustable and it probably has a way to defeat it in the event you want to stop the engine before it times out. Have you allowed it to run for a period of time to see if that is the situation?

Hi

I have allowed enough time to confirm there is something wrong in the change over.

There are various sensors in the panel that could make this happen. One, of course, monitors the incoming power to see if it is 1) - Present; 2) - At the correct phase and voltage; 3) - Sustainable and 4) - Stable. If any of these factors is not suitable, it will not allow the retransfer of the power from the generator to the normal. Usually, there is a small handle that you can use to induce the change in the operation of the system from stand-by emergency power to normal power and vice versa. It may be a small loose rod with a rubber tip. You slip the end of the rod into one of the holes in the rotary transfer mechanism and simply pull it down. This will shut down the system if you move it to the "Off" position, or it can put the system into the "Normal" mode. It should already be in the "Emergency" mode if it is still running. After you put it into the "Normal" position, the generator may continue to run for the cool-down feature I described in my last reply. However, the power should have transfered to the Normal source. If the power is not evident when you put the handle in that position, then it would appear that you still do not have commercial power available, hence the running of the engine. Also, make sure that you have all three legs of the incoming power (for three phase - two legs for single phase). If one leg is out, possibly due to a fuse blown in one leg, the machine will not recognize the power and will stay on the emergency power supply. If you are not sufficiently familiar with this particular ATS, I would suggest that you contact the vendor or the manufacturer for more help. Good luck.

Thanks When the utility power supply restored, the relays tries to switch to the utility power supply side three times finally it fails and remain in off position (neither utility nor generator connected to the load) and the LED between utility power supply and load starts to brink and the generator do not stop when that alarm exists until reseted.

Read the manual for the ATS controller. There could be a setting that forces you to perform some command at the controller to restore the system to normal operating conditions (rather than it happening automatically). It may be as simple as that. In some cases an operator may want to have their electricians control the return to normal rather than let the ATS do it.