Timing Relays for 30 days

[RNLENI]

I have a panel that controls two 60HP Motors. One duty and another one stand by. No plc. Just Relays. The Motors need to change over every 30 days.
What will be the best timing relay to use for this purpose? or any other better device?

 

[petersonra]

Here's a link to some timers.

https://www.automationdirect.com/adc/shopping/catalog/relays_-z-_timers/timer_relays

Keep in mind that most of these will probably reset on power failure. If that matters to you, you might be better off just getting a motorized timer. I think they are still available. On the other hand you can buy pump alternating relats that are already set up like this. Why make something yourself that you can buy for the same price.

 

[kwired]

Cheap PLC that has battery backup ability? Might cost similar to anything else you may find but can be customized the way you want it to be.

As mentioned reset upon power failure is something to consider and the battery back up ability maybe eliminates this problem - as long as battery is good.

 

[EC Dan]

You could use something like a TORK electronic timer. It has it's own battery backup and a max time setting of 365 days.

 

[kwired]

You could use something like a TORK electronic timer. It has it's own battery backup and a max time setting of 365 days.

does it have a double throw contact or would one need to use a control relay for alternation of the loads?