Relay Current Requirements

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dragonbat13
Posts: 321
Joined: Tue Feb 27, 2007 1:38 am
Location: Southwest Louisiana

Relay Current Requirements

Post by dragonbat13 »

I am using this transformer for my D'lite build:

http://www.mojotone.com/amp-parts/Trans ... ransformer

I am wondering if 3A @5V will be able to supply two of Colossus' relay boards using his regulator/rectifier board.

What would the current requirements be for these relays, using an LED at the footswitch?

A link to a good source for relay info would be cool too if anybody knows of any out there.

Thanks
10thTx
Posts: 1863
Joined: Sat Dec 30, 2006 1:13 am

Re: Relay Current Requirements

Post by 10thTx »

Here is a link to good information about relay switching along with schematics, layouts, and photos.

http://el34world.com/Forum/index.php?topic=14348.0

With respect, 10thtx
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Colossal
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Re: Relay Current Requirements

Post by Colossal »

dragonbat13 wrote: Wed Aug 16, 2017 8:41 am I am using this transformer for my D'lite build:

http://www.mojotone.com/amp-parts/Trans ... ransformer

I am wondering if 3A @5V will be able to supply two of Colossus' relay boards using his regulator/rectifier board.

What would the current requirements be for these relays, using an LED at the footswitch?

A link to a good source for relay info would be cool too if anybody knows of any out there.

Thanks
You will be fine using the 5VAC rectifier winding to provide power to the relay power supply board. The board has very low forward voltage drop diodes on it, plus the high current rectifier winding will usually run a little hotter voltage-wise with a very small load such as what the entire relay and LED loads present. It has been done many times before. The LEDs and relays themselves pull tens of milliamps. The only caveat is that if you use the 5VAC rectifier winding for your relay circuit, you cannot also use it for rectifcation.
Last edited by Colossal on Wed Aug 16, 2017 12:22 pm, edited 1 time in total.
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Colossal
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Re: Relay Current Requirements

Post by Colossal »

Double post :x
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dragonbat13
Posts: 321
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Location: Southwest Louisiana

Re: Relay Current Requirements

Post by dragonbat13 »

Colossal wrote: Wed Aug 16, 2017 12:19 pm
dragonbat13 wrote: Wed Aug 16, 2017 8:41 am I am using this transformer for my D'lite build:

http://www.mojotone.com/amp-parts/Trans ... ransformer

I am wondering if 3A @5V will be able to supply two of Colossus' relay boards using his regulator/rectifier board.

What would the current requirements be for these relays, using an LED at the footswitch?

A link to a good source for relay info would be cool too if anybody knows of any out there.

Thanks
You will be fine using the 5VAC rectifier winding to provide power to the relay power supply board. The board has very low forward voltage drop diodes on it, plus the high current rectifier winding will usually run a little hotter voltage-wise with a very small load such as what the entire relay and LED loads present. It has been done many times before. The LEDs and relays themselves pull tens of milliamps. The only caveat is that if you use the 5VAC rectifier winding for your relay circuit, you cannot also use it for rectifcation.
I remembered somewhere along one of my old threads where there was an issue with current requirments, but I thought the load of the relays and leds and everything I wanted to do was never gonna hit the 3 amp mark. That would be a heck of a relay setup to pull that current.

I remember it being said it was an issue using a twin reverb power transformer. Perhaps that was due to a 100 watt blackface transformer which wouldnt have the rectifier tap since its rectifier would be solid state.
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