Programmatically Control Power to Certain Device

I was wondering if there was a way or a device to programmatically control whether electricity to a certain device is enabled or disabled. Basically, it would work like Rev’s PDH’s switchable channel, but for a high-current channel.

For example:

The power to ‘Device A’ needs to be switched on or off during or before the match. As the PDH has no built-in switchable channel for the high-current channels, what kind of external device would I need between these two devices?

I am looking for something that would be able to enable or disable the power going through it, preferably controlled over the CAN bus (or PWM).

What kind of device are you running that is higher current than the switchable port?

Anyways, what you are looking for is a relay.

Somewhat depends on your application, but this one should work :

You can probably find cheaper versions. You want to make sure that the relay has enough output current capacity for your application, rated for 12VDC, and has 5v as an option to control it.

Depending on the power quality your device needs, you might also get away with using a brushed motor controller like a Spark Max or Talon SRX, set to 100% duty cycle, to turn power on and off. That’s how we trigger the 12V valves in our T-Shirt cannon.

1 Like

If you want to build an inspection-passing robot, then I’d start with R503B

B. relay modules,
a. Spike H-Bridge Relay (P/N 217-0220 and SPIKE-RELAY-H),
b. Automation Direct Relay (P/N AD-SSR6M12-DC-200D, AD-SSRM6M25-DC-200D, ADSSR6M40-DC-200D), and
c. Power Distribution Hub (PDH) switched channel (P/N REV-11-1850) for controlling
non-actuator CUSTOM CIRCUITS only,


Note: They don’t manufacture Spikes anymore, but most sufficiently old teams should have tens to hundreds of them stashed away in their “old electronics we never touch” bin. They can also be acquired on ebay. Quite a fan of the spike, but the AD relays may be a better option if you are looking for a part that isn’t several years past EOL.

1 Like

Can someone explain to me why R503.B.c is in the rule at all?
R503 explicitly states that its talking about what is allowed to switch actuators, not custom circuits.

To the OP: as long as the circuit that is connected to the device to regulate power in your diagram is a custom circuit you can use any relay you’d like and it should do the trick. (and also be legal)


Maybe we’ll all be lucky and REV ION phase 2 will bring us a CAN enabled/controlled relay!

I swear I recall Greg mentioning something (in the last year or so) about at least a couple more control system/electrical parts in the works.

All I can tell you is that the phrase “for controlling non-actuator CUSTOM CIRCUITS only” was added in Team Update 01.

That depends on what OP is trying to power. R625 prevents the use of custom circuits for powering “motors and actuators”.

I’ve sent an email to FIRST suggesting that this rule be slightly updated and clarified for next year.


This topic was automatically closed 365 days after the last reply. New replies are no longer allowed.