How To's

Relay Wiring for "H" Bridge Relays


This section shows wiring for a control system using EP2R-B3G1 6V "H" Bridge Relays. These can be found at The Electronics Goldmine (Item# G14951) These are cheap at under a $1.00 and this setup only requires 1 Relays for every Thruster used which saves space in the contol box. These only have a 6 volt coil but I've been using 12 volts and haven't had any problems yet. This system as shown will allow for basic on/off control of 3 thrusters and one light but more could be added easily.

This is what the bottom of the "H" Bridge Relay and bottom of a Standard DPDT Relay consists of.

You will need 3 "H" Bridge's for the Thrusters and 1 DPDT Relay for the Lighting. I usually line them up and glue/tape them together to make it easier to solder all of the connections.

Start by soldering on wires to connect all of the Pos. and Neg. Poles as shown.

Then you will connect one side of each coil to the next.

The next step will be connecting your actual Thrusters. Normally the Relays will be sealed in a box (not shown) and the thruster wires will have to be feed into that box before soldering them on. (as well as the rest of the wires in the next steps) You can see how I did this on my Retrofit Seafox Control Box Page.

Next you will connect the wiring for your lighting. The Positive comes from the last relay and the negitive wire will connect to the NC pole of the SPST Relay as shown.

The Main Power Wires from your Tether are connected next. The main power wires are shown here tied into the frist relay but they can be connected to any of the relays if it's easier. I use 16 Gauge speaker wire for main power because it's cheap and readily available. But the gauge used would depend on the length of your Tether becuase of voltage drop.

Then you will connect the common Positive for the relay coils.

The last wires to connect are your control wires from your tether. These can be anything from cat5 wires to phone wires, I use the latter, again because they are cheap and available anywhere.

This is an overview of what the entire setup should look like.


If you have any other questions feel free to E-mail me, or if you actually use this setup let me know how it worked out for you.
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