This is a placeholder topic for “10A 24V DPDT Cradle Relay” comments.
High power DPDT relay suitable for switching loads up to 10A. Designed to suit the SY-4064 DIN rail mounting cradle.
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What’s the minimum switching voltage? Will 5V DC be enough to activate the relay?
I have a PC which controls a lighting system, but the lighting system is powered by a separate supply (maximum power draw from the lights is 5V, 10A) and I need the power to the lights to cut when the PC is off. So I’m trying to use power from a USB port to activate a relay to connect power to the lights, only when the PC is turned on.
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Hi Lachlan
The heading for the part suggests operating voltage to be 24V but the info on Core web site does not specify that. With a coil resistance of 640Ω I think it may be 24V as 5V would only be about 8mA, way not enough to operate this type of relay. The pic looks similar to the Omoron LY series which may yield some clues as to minimum (must operate) operating voltage.
Cheers Bob.
PS: For Core… Sometimes nice to have the whole picture.
EDIT: the coil resistance of 640Ω and max coil power of 900mW equates to 24V
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Hi Bob,
Thanks for your help, I ended up finding a more suitable relay which was clearer on the specs. I’d rather not take the risk with this one.
Cheers
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Raspberry Pi at one end. K-Rain or equivalent 24 volt AC solenoid at the other end. What do I put in the middle? Power supply?
I started this project with 12 volt DC but UV resistant irrigation solenoid valves are just not available locally.
Hi Peter
A 24VAC power supply with enough grunt to drive your solenoid(s). Allow some for future expansion.
You are switching AC voltage so you should be able to use a Solid State Relay (SSR). These require an input voltage of usually 3 to 30VDC at just a few mA to switch them so should be able to operate directly from your RPi.
Check all specs prior to purchase also the ability of RPi to switch the SSR directly.
There have been other posts regarding 24VAC for operating irrigation solenoids in the not too distant past. You will get a lot of info there including power supply type, SSR type and switching.
Cheers Bob
Hello Bob,
Thank you for the suggestion. I looked at SSR SSR-60DA Solid State Relay | Core Electronics Australia. $12.05 * 4. Ouch.
I looked around and decided to use $3.55 https://core-electronics.com.au/5v-4-channel-relay-module-10a.html. The switching will only be once or twice a day and the amperage 0.4 peak.
Hi Peter
Good luck. I have had a bit to say about operating this sort of thing on 3.3V with a 5V relay so will say no more.
A tip. Even though your RPi is 3.3V logic I think you can apply 5V to the relay circuit by removing a link. Do this if you can and you will have a better chance with reliability.
Core don’t publish a circuit so you will have to do your own research on this device. Someone else may have reversed engineered this and care to share but I have not personally sighted one.
Cheers Bob
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Hi Peter
Have found (from a previous discussion) this link which gives a better description and a schematic.
Cheers Bob
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Thank you for the PDF. I will test the following options.
It is sometimes possible to use this relay boards with 3.3V signals, if the JD-VCC (Relay Power) is provided from a +5V supply and the VCC to JD-VCC jumper is removed. That 5V relay supply could be totally solated from the 3.3V device, or have a common ground if opto-isolation is not needed. If used with isolated 3.3V signals, VCC (To the input of the opto-isolator, next to the IN pins) should be connected to the 3.3V device’s +3.3V supply.
NOTE: Some Raspberry-Pi users have found that some relays are reliable and others do not actuate sometimes. It may be necessary to change the value of R1 from 1000 ohms to something like 220 ohms, or supply +5V to the VCC connection.
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