What are the current preferred relays for FRC to do an on/off job

In the “good old days” we had the spike H-bridge relay to connect to the roborio. We had one once and we are unable to locate it. Back then it was sold by REV but its not found on their website or anywhere on the internet it seems so is it ok to use something like this

https://www.automationdirect.com/adc/shopping/catalog/relays_-z-_timers/solid_state_relays/panel_mount_relays,hockey_puck_style,10a-75a(ad-ssr6_series)/ad-ssr6m12-dc-200d
We want to drive this solenoid
https://www.jameco.com/z/SH-T2551L-Solenoid-12V-Pull-Type-Solenoid-10-Watt_2196748.html
Or do we have to roll out own? (maybe a 2n3904 boosting the voltage from 5 to 12V and then driving a mosfet plus a couple of resistors of course)

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In the game manual there’s a specific rule about what relays you can use.

Relay Modules
i. Spike H-Bridge Relay (P/N: 217-0220 and SPIKE-RELAY-H)
ii. Automation Direct Relay (P/N: AD-SSR6M12-DC-200D, AD-SSRM6M25-DC-200D, ADSSR6M45-DC-200D)

The first link you posted won’t load for me, so if it’s to one of the ones listed here you should be good. If you want a Spike I have a few sitting under my bed in a box and would be happy to ship one to you. No idea how long shipping would be, I’m in Seattle WA.

Side note, I’ve never heard of Spikes being sold by REV, pretty sure it was always VEX. I could be wrong, I wasn’t involved in FRC when Spikes were still mainstream.

Spike Relays are/were from VEX/IFI.

If you need one let me know. I just did an inventory and found a few that I doubt we’ll ever use.

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According to R30, you must control the ELECTRICAL SOLENOID with one of the legal motor controllers, relay modules, or pneumatics controller(s) listed in R29. So if you want to use a relay it has to be a Spike or one of the legal AD relays, as @Gavatron77 said. There’s no reason you can’t use a “dumb” motor controller and only command it to 0% or 100%, though. Legally you could also use the PCM to control it, but at 12V 10W it will pull 833mA, which is more than the 500mA total from the PCM.

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looks like the right part. I doubt the part number is case sensitive

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oh…yeah…I have a couple Spikes sitting in front of me, too.

Right - VEX its old age setting in.

I somehow missed the part number. Thanks for pointing that out.

Thanks for the rules pointer.

Good idea with the motor controller we probably have one lying around I will check monday if not one of the other 2 it is. The spikes were nice but we did not use one since 2013 or 12 I think

If you’re looking at allocating a PWM channel to a function where you want to use a mechanical solenoid, seriously consider a servo. These are available with far greater pulling force*distance than legal solenoids, would likely be a lot lighter than a solenoid + motor controller, and would not take up a full PDP slot.

I was told they are all 6volt. Which one do you have in mind. and we have plenty PWM channels as the MC are on can

Yes, but they can act over a longer time, so can get more work done. Most solenoids only act over a few tens of milliseconds. If you can spare a couple tenths of a second (or longer), go servo.

We haven’t used a serve in FRC so which one is a good one and how do you solve the 6V problem. we are looking for the solenoid to be activated 2-sec to release the ratcheting brake on the climber when we extend our hook

What 6V problem are you referring to? The RIO provides some current at 6V on the PWM middle pins; if you need more than that, the REV servo module will convert 12V to 6V for you. If you have 2 seconds, you can get way more work out of a servo powered from the RIO than a legal solenoid.

Thanks we will explore that.

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The RoboRIO 6V lines in the PWM ports can provide a combined 2.2A (13+ Watts) per page 6 of this document:

The REV servo module can provide 15A/90W of power per the REV servo module web page:

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Without reading too much into the rules like at all for this year, in the past teams have used the PCM to control leds/custom circuits, is that an option?

Gonna have to check on that and check the current. So some research required. Rev servo draws 2A max and the PCM puts out 2A peek thats cutting it short so we need 2 so if we do servo it will have to be the servo module. As we need 2 that would make a potential 4A which would also exceed the combined load for the roborio. so its either going to be the solenoids or the servo with the REv Dc/Dc converter.

If you just have the one servo, the RIO can power it. Motor controllers don’t use the 6V line.