Transfer switch question???

mbrower wrote:


Excellent response! Love this kind of feedback.

I currently have 2 transfer switches. One is a 50A with priority to shore power (as stated before) that will stay on shore power regardless whether the inverter or generator is on. It will only switch if shore power is off. Once shore power is returned, the switch will transfer power back to shore power. Alternate power should never backfeed to shore power as long as the transfer switch is working correctly.

The generator and inverter are on the alternate power feed and is being switched by a 30A transfer switch. Priority is given to generator after 40 second time delay.

I think you may believe the generator and shore power feed one input side of the transfer switch and this is not the case. Shore power feeds one input and inverter/generator feeds the other input though a separate 30A transfer switch. All inputs are separated from one another so no backfeeding is possible with properly operating transfer switches. Am I still missing something?

Mark

First and foremost, thanks for the compliment.. .you just made my day. :-)

Now back to the issue.

I think I'm following your line of thought. The inherent logic would certainly serve the projected goal. However, you did not say where you will get the control power to energize/deenergize the transfer switches.


Are you powering them from the shore power or from the inv/gen?

Since you stated that your dominant power would be shore power, I assume that both 30A transfer switch and 50A transfer switch are controlled by shore power. Being plugged in to the pedestal would ignore other available power source. Which is fine and dandy as long as there is power at the pedestal.

Now, here is the kicker: Although this instance is moot and hopefully won't ever happen in your case, the possibility still exist. If I can quote Murphy's Law: "Anything that can happen will happen".

What's gonna happen if (God forbid) you lost power completely or experience a prolonged power outage, your battery is down while the auxiliary is setting idle. Whatever state you transfer switch is in prior to the power failure will remain that way. Firing up the Auxiliary power would not do any good either because the transfer switches are looking for the pedestal power which of course God knows when it's coming back.

I just hope it won't coincide with Jesus's Second Coming. :-)

Cheers!