Mist coolant wiring 24vdc

[garybergin288]

i could not find a wiring schematic for a mist solenoid i am using 24vdc solenoid NC the solenoid will be external from the control box i just need help with where and how to wire it up tia

[Richards]

The first step in using an unknown solenoid (or any other device) is to understand how it works. You said that the solenoid is 24VDC N/C. Hook it up to 24VDC through a simple toggle switch. See what the solenoid does when power is applied and when power is disconnected. Each relay on the relay board supplied with the Acorn has a N/O contact and a N/C contact. Connect your solenoid to the relay so that it turns on when you want it to turn on by connecting the leads as it the relay were a simple toggle switch.

[ShawnM]

There are examples on wiring solenoids and pumps on the "standard connections" diagram #S14953. As noted, it's wired just like a switch. Apply power through the relay when you need it and turn that output off when you don't.

[tblough]

Don't forget to add a snubber to the coil circuit.

[ShawnM]

Don't forget to add a snubber to the coil circuit.

Yes, a snubber or in this case a diode across the 24 VDC coil is a MUST. It's not an option.

[Richards]

Here's a simple schematic that might help. L1 is the solenoid. D1 is a diode (1N4002 - 1N4007). SW1 is the relay module on the relay board. When the relay is turned ON, power flows through the solenoid. When the relay is turned OFF, induced voltage (surge) is shunted back through the diode to the power supply.

[carbuthn]

I ended up using:
https://www.automationdirect.com/adc/sh ... 11-ls24-3r
https://www.automationdirect.com/adc/sh ... s-3212-24d
You don't have to have the cable, but it has the surge protection built in. I powered from the 24vdc supply through a fuse to (used a separate power supply) a relay common, from the NO contact to the solenoid, from solenoid to ground.

I also purchased the fittings and tubing from them.

[garybergin288]

Here's a simple schematic that might help. L1 is the solenoid. D1 is a diode (1N4002 - 1N4007). SW1 is the relay module on the relay board. When the relay is turned ON, power flows through the solenoid. When the relay is turned OFF, induced voltage (surge) is shunted back through the diode to the power supply.

solenoid.png

thank you for your reply does the direction of the diode matter? the solenoid wires are not polarized so they can be connected either way and im just wondering how to wire in the diode thanks

[ShawnM]

If it's a 24VDC solenoid it DOES matter which way the power is hooked up. The plunger moves towards the winding and you may be opening the valve when you need to close the valve if you reverse the wiring so be careful in how you wire it. Determine which way works for your application and then install the diode per the diagram posted. The line across the top of the triangle in the diode symbol is the band on the diode.

A spring return valve as linked to by carbuthn is a better option for solenoid valves.

[cncsnw]

The diode should be installed as in Mike's diagram: bar towards +24V. If you install the diode backwards (bar towards 0VDC), then it will act as a short circuit, bypassing the solenoid coil.

ShawnM: although this is counterintuitive, my experience and observation is that 24VDC solenoid coils are generally not sensitive to polarity: you can wire them either way, and they work the same.