directlogic 05 relay, triac etc

Hello all,
I am running a 205 to control a coil (among other things) The coil is 110vac and draws an amp.

The contact time varies but it is usually about 5 seconds, a off period of anywhere from 5 sec to 2 min. and repeat.

The relays in the 05s indicate about 500K closures before they burn out. The number of cycles can add up quickly I would like to extend that time if possible.

Should I use the standard 05 AC relay module and just change it out when it goes bad?

Use a triac output ? Use transitor output to drive a dc relay?

Thanks,

TJ

For that size load and that duty cycle I would use an interposing relay driven by a solid state output module. Whether 24 VDC or 120 VAC is up to you.

Sounds like a heater application. If you are going to stay with original 110VAC control, use a Triac output on the PLC.
Is your coil a mercury relay or contactor? Mercury will have long life, but a contactor will wear out quickly. If contactor, consider replacing with SSR.

My preference with heaters is transistor output and SSR. But I wouldn't do a transistor-SSR-contactor.

Should I use the standard 05 AC relay module and just change it out when it goes bad?

Click to expand...

It appears that your Automation Direct DL-205 relay module replacement would cost about $8.63 per relay. Because you already have it wired up (exisiting), it would cost something in labor to change the wiring. I think at that price, I would just buy a couple of spare modules. No extra wiring, no extra parts, cheap, simple, and easy-to-replace plug-in modules.

http://www.automationdirect.com/adc...ar_PLC)/AC-z-DC_I-z-O_(Relay_Outputs)/D2-08TR