load switch

[e67]

Some people might have a concern about 2 larger loads turning on at the same time on an inverter...it might be pushing the rating somewhat..
Is there an electronic switch people use that is wired up with the 2 loads passing thru ,that will only allow one load to run and then when its finished(like a well pump)
it will enable the other load...but not both at the same time...?

 

[sunshine_eggo]

Some people might have a concern about 2 larger loads turning on at the same time on an inverter...it might be pushing the rating somewhat..
Is there an electronic switch people use that is wired up with the 2 loads passing thru ,that will only allow one load to run and then when its finished(like a well pump)
it will enable the other load...but not both at the same time...?

The only thing that comes to mind are some EV chargers designed to piggyback off an existing dryer connection - allows only one or the other to operate.

I can't think of anything specific for a general purpose, but it would be pretty easy to do it manually with relays.

Device 1/Relay 1
Device 2/Relay 2

Relay 1 must be closed for device 2 to operate.
Relay 2 must be closed for device 1 to operate.

Both relays normally closed (NC) when not energized.

Device 1 turns on, relay 1 on, relay opens and device 2 not allowed to turn on.
Device 2 turns on, relay 2 on, relay opens and device 1 not allowed to turn on.

The only time this would not work is if both turn on at EXACTLY the same time.

 

[Ampster]

There are severak EVSE switching devices to run EVSEs off dryer outlets. I believe they can be ordered with different plug configurations. The typical programming is that the dryer is given priority and the EVSE is secondary. I have not taken mine apart but I am sure it uses some load activated relay to switch the two hot legs. The one I have is called NeoCharge but there a quite a few that come up with a simple Google search for "dryer outlet EVSE"
EDIT: Hedges, in an earlier comment, outlined a simple relay configuration that could work.

 

[wpns]

It's easier to give one priority (if the well pump is running, disable the Air Conditioning), but you need loads that can handle frequent power removal, and (if not the simple example above), a set of rules about which one has priority, which one starts first, if each is interruptible, etc.

 

[robbob2112]

https://www.amazon.com/Aumtoni-SW202-Reversing-Contactor-Albright/dp/B0BX8XCRDQ/

Something like a reversing contactor might do the job?

 

[Ampster]

Something like a reversing contactor might do the job?

He would still need a trigger. Reversing contactor is typically used on DC motors to change polarity to make them run in reverse. That is a 400 Amp DC device. The power in this application is AC and could easily be accomplished by less expensive double pole relays that can easily switch AC and would cost a lot less.

 

[DIYrich]

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[robbob2112]

The simplest solution would be an interlock breaker, flip one way for well pump, the other way for the other high load

 

[wpns]

The simplest solution would be an interlock breaker, flip one way for well pump, the other way for the other high load

But the OP (quite reasonably) wants it to be automatic. A current sensor (CT switch?) on the high priority device that interrupts the supply to the low priority device is pretty trivial.

 

[cs1234]

There are severak EVSE switching devices to run EVSEs off dryer outlets. I believe they can be ordered with different plug configurations. The typical programming is that the dryer is given priority and the EVSE is secondary. I have not taken mine apart but I am sure it uses some load activated relay to switch the two hot legs. The one I have is called NeoCharge but there a quite a few that come up with a simple Google search for "dryer outlet EVSE"
EDIT: Hedges, in an earlier comment, outlined a simple relay configuration that could work.

Something like this NeoCharge but able to be hardwired in would be fantastic for a 10kw inverter needing to power multiple ac units, water heaters, etc..

 

[e67]

I can make an interlock breaker of my own design and that will be good enough..but I am going to house it separately from a load center.
I have decided not to mix my solar and grid systems at all. Less worrisome ,more work but not prodigious..