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Mini Maestro toggle 12VDC relay

I am trying to use a channel as output to toggle the SPDT Relay Carrier with 12VDC relay.

The relay lights up when I set the channel to high but the relay doesn’t toggle?

I am wondering if I am using the wrong device to for the switch.

I am using a LED Fader module that uses 12VDC to fade an LED but the switch just contacts one side of the the power. I think this is low voltage (25mA) connection so there is very little current going through the relay.

Do I just need a digital switch ?


All you should need to do to activate the relay is power VDD from 12V and apply a control voltage to the EN pin that exceeds approximately 2.5V, so something as simple as a digital switch could work, but a Maestro pin configured as a digital output should work for supplying the EN signal too.

I suggest confirming that your relay is working (separately from the Maestro) by just directly applying an appropriate a voltage to EN. If the relay is working, please check that you are configuring the Maestro channel connected to EN as an output, and try setting its target value to something greater than 1500 μs using the Maestro Control Center. You can find more information about the Maestro’s channel settings in the “Channel settings” section of the user’s guide.

If you continue having trouble, please post some pictures that show the full setup, including how the Maestro is powered and connected to your relay. Also, can you post a copy of your Maestro’s settings file? You can save a copy of your settings file from the “File” drop-down menu of the Maestro Control Center while the Maestro is connected.

- Patrick

This LED connection is part of a script that controls 5 servos using channels 0-4. I have set channel 5 as output and set it to 8000 when I want to turn on the relay and 0 when I want to turn it off. The LED is turned on at the beginning of the script and off at the end. The power supply of the maestro is 6VDC 3A.

this device allows the 12VDC LED to fade up when turned on and fade down when turned off.

Since the LED requires 12V I figured I’d need the relay.

Can you clarify what you are powering the relay’s VDD pin from and post some pictures that show the full setup like I requested in my last post?

- Patrick

Does this help?

If your system is wired according to that diagram, then VDD is receiving only 6V. Since you have a 12V relay, you need to supply VDD with 12V.

- Patrick

or I could purchase a 5V relay instead?

If you use a 5V relay, then you would ideally connect VDD to a 5V source. However, 6V is close enough (120% of 5V) that it is probably still okay. The datasheet for the 5V relay we use (available on the product page under the “Resources” tab lists the maximum operating voltage as “130% of rated voltage at 85°C”.

- Patrick