Sean Halley
Member
Hey guys - quick question for those who know about standard hookups for relays.
I've got some of the little 12v coil 4-pole relays (rated at 125v AC for 5 amps on the poles) guys use in audio preamps - and I built one into a box on my guitar pedalboard for moving a pedal into two places in the signal chain.
I know that the coil can kick back enough to hurt sensitive circuits (saw it shut down the switcher I was using), so I put a 4007 diode on the two 12v leads of the relay to protect the switcher. The white band end is towards the positive connection, so nothing should travel back down that lead to the switcher and hurt it (the switcher is inside of an expensive MIDI controller I don't want to replace .
It was working fine with a couple of caveats, but the relay died the other day. Before I simply replace it with another one, I want to make sure I'm doing the right thing.
So a couple of questions:
1. I've got a regulated 400ma 12V tap on my pedalboard powersupply that wouldn't operate the relay. The actual meter reading on the two available 12v taps were 11.9 V and 12.1. Both of those taps wouldn't trip the relay.
2. I have another pedalboard supply with an unregulated 12v tap, that shows up as 12.5v - and it trips the relay just fine. I ended up using a wall wart 12v 300 ma supply that worked great for a few hours, and then the relay died. Is this normal, do you think? Do you think the 11.9/12.1V supply wouldn't trigger the relay because of current or voltage? Kind of curious.
Also, is there a better (or the right!) way to use a diode to protect the switcher from when the relay's coil shuts off? I have bigger diodes lying around, if that helps. I connected the diode right to the leads of the switcher, so perhaps I should harness it differently? Connect it differently?
Anyway, thanks as always for any help in advance - the diode was a guess of mine until I did some reading and found out that it's normal. I just need to know what I'm doing wrong, or if it's just a damn normal relay failure.
Thanks guys!
S..
I've got some of the little 12v coil 4-pole relays (rated at 125v AC for 5 amps on the poles) guys use in audio preamps - and I built one into a box on my guitar pedalboard for moving a pedal into two places in the signal chain.
I know that the coil can kick back enough to hurt sensitive circuits (saw it shut down the switcher I was using), so I put a 4007 diode on the two 12v leads of the relay to protect the switcher. The white band end is towards the positive connection, so nothing should travel back down that lead to the switcher and hurt it (the switcher is inside of an expensive MIDI controller I don't want to replace .
It was working fine with a couple of caveats, but the relay died the other day. Before I simply replace it with another one, I want to make sure I'm doing the right thing.
So a couple of questions:
1. I've got a regulated 400ma 12V tap on my pedalboard powersupply that wouldn't operate the relay. The actual meter reading on the two available 12v taps were 11.9 V and 12.1. Both of those taps wouldn't trip the relay.
2. I have another pedalboard supply with an unregulated 12v tap, that shows up as 12.5v - and it trips the relay just fine. I ended up using a wall wart 12v 300 ma supply that worked great for a few hours, and then the relay died. Is this normal, do you think? Do you think the 11.9/12.1V supply wouldn't trigger the relay because of current or voltage? Kind of curious.
Also, is there a better (or the right!) way to use a diode to protect the switcher from when the relay's coil shuts off? I have bigger diodes lying around, if that helps. I connected the diode right to the leads of the switcher, so perhaps I should harness it differently? Connect it differently?
Anyway, thanks as always for any help in advance - the diode was a guess of mine until I did some reading and found out that it's normal. I just need to know what I'm doing wrong, or if it's just a damn normal relay failure.
Thanks guys!
S..