BloodShot420
Well-Known Member
hey IamS5oned...
good to have a bored electrician on the boards... I got a question that maybe you could help me with...
I run my grow room with a PLC... it turns on the fans, lights, water pumps, and monitors the door switch and some other stuff... I run a closet in a small house, so its gotta be super stealth. So - i used to have 2, 1000w systems in there, and used these little solid state relays to turn them on/off. The solid state relays are rated at 25A at 240v (they will work with 120v too) they turn on with a DC signal voltage that comes from the PLC...
well - i'm having some rather odd problems with my PLC... mainly just one problem, when its not connected to the computer - its not really running.. it will not turn things on at the right time with no computer connected to it... (like it forgets the time or something)...
so here's the thing - when the solid state relays fail - they get hot, and then when you remove the DC signal voltage, the relay is so hot or whatever, that the load current will not stop... my question is - could the load current go back through the DC voltage lines into the PLC at some point? they failed a few times before i figured out what was going on, so they lights ran an extra hr or two on some days.
i had the relays mounted on a piece of aluminum with some small fans blowing on them and some thermal compound behind them so they aluminum would dissipate some of the heat... but still they arent quite enough to run the 1000w systems.... i changed up my closet to 2 digital quantum ballasts at 600w each - and i had a couple of instances during veg that the solid state relays failed again...
also, is there something i can do using 2 relays to turn on one light? I'm wondering if i can take the load wire, and split it, run it to 2 different SSR's and use 1 DC control wire to turn both SSR's on at the same time... will that divide the load through each SSR?
I never really understood the downsides of SSR's until i bought 50 of them - i love the fact that they are dead silent though Thanks for any info you might have...
good to have a bored electrician on the boards... I got a question that maybe you could help me with...
I run my grow room with a PLC... it turns on the fans, lights, water pumps, and monitors the door switch and some other stuff... I run a closet in a small house, so its gotta be super stealth. So - i used to have 2, 1000w systems in there, and used these little solid state relays to turn them on/off. The solid state relays are rated at 25A at 240v (they will work with 120v too) they turn on with a DC signal voltage that comes from the PLC...
well - i'm having some rather odd problems with my PLC... mainly just one problem, when its not connected to the computer - its not really running.. it will not turn things on at the right time with no computer connected to it... (like it forgets the time or something)...
so here's the thing - when the solid state relays fail - they get hot, and then when you remove the DC signal voltage, the relay is so hot or whatever, that the load current will not stop... my question is - could the load current go back through the DC voltage lines into the PLC at some point? they failed a few times before i figured out what was going on, so they lights ran an extra hr or two on some days.
i had the relays mounted on a piece of aluminum with some small fans blowing on them and some thermal compound behind them so they aluminum would dissipate some of the heat... but still they arent quite enough to run the 1000w systems.... i changed up my closet to 2 digital quantum ballasts at 600w each - and i had a couple of instances during veg that the solid state relays failed again...
also, is there something i can do using 2 relays to turn on one light? I'm wondering if i can take the load wire, and split it, run it to 2 different SSR's and use 1 DC control wire to turn both SSR's on at the same time... will that divide the load through each SSR?
I never really understood the downsides of SSR's until i bought 50 of them - i love the fact that they are dead silent though Thanks for any info you might have...