Power supply turn off when latching solenoids switches ON?

Thread Starter

izzarasul

Joined Jul 1, 2021
2
I have two 24VDC, 1.54A latching solenoids. I connected them both in parallel with power supply (80V, 80A). But when i turn ON the power supply it immediately turn off. However, when i connect a single latching solenoid with power supply it works fine. Is it necessary to use two power supplies for two latching solenoids or there is a way to use both with one?

Need Help!
Thanks in advance.
 

Dodgydave

Joined Jun 22, 2012
10,095
Your psu is 80V and you're putting a load rated at 24V, so it's going to take more current, you need to use a 30V max at 5A ideally.
 

Yaakov

Joined Jan 27, 2019
3,769
Your description is confusing. A 24V 1.54A coil would have a resistance of about 15.54Ω, two in parallel would drop that to 7.77Ω. 80V into 7.77Ω would get you about 10.296A.

If your supply can provide 80A it shouldn’t shut down, it should just produce a lot of smoke as the coils or wires burned.

Are you sure about the ratings of the supply? 80V at 80A is 6400W! That’s a massive supply.
 

LesJones

Joined Jan 8, 2017
3,573
You could connect the two relay coils in series and drop the extra 32 volts with a resistor of 21 ohms. The resistor would disipate about 50 watts so I would suggest using 100 watt rating resistor. A better solution would be to forget the 80 volt power supply and buy a 24 volt one.

Les.
 

Reloadron

Joined Jan 15, 2015
6,227
Why are you powering a 24 VDC coil (assuming it is 24 VDC) using an 80 volt source? You are exceeding the rated coil voltage by three times plus. This alone makes no sense? You need to better explain exactly what your goal is and make and model of power supply as well as the solenoids would help.

Ron
 

Janis59

Joined Aug 21, 2017
1,357
Seems reason is the same when I plug my palmtop to USB to recharge. It cyclically switches off and on without of any lading. However from "dumb" 0.5 A transformer it lading-up without of any problem. Just - power source intelligence sees the consumer really may get 2A therefore over-current security switches it out. Your case - PS gives 1/10 from consumer demand, thus the problem is more violent.
 

MisterBill2

Joined Jan 23, 2018
9,908
I find an 80 volt 80 amp power supply rather hard to believe. Possibly 80 volts and 80 watts. And why would any person connect a 24 volt device to an 80 volt supply?? That makes no sense at all. None of the original statements make sense.
Possibly it could be a power supply rated at 80 watts mains input. But at this point all is guessing.
 

Thread Starter

izzarasul

Joined Jul 1, 2021
2
I have two 24VDC latching solenoids. I connected them both in parallel with power supply (80Vmax, 50Amax). The power supply is set to supply 24 V and 5A max to load(solenoids). But when i turn ON the power supply it immediately turn off. However, when i connect a single latching solenoid with power supply it works fine ( 1.5A current pass through the solenoid). Is it necessary to use two power supplies for two latching solenoids or there is a way to use both with one?

Need Help!
Thanks in advance.
 

LesJones

Joined Jan 8, 2017
3,573
izzarasul, You have changed your story from post #1. In post #1 you say you are using a power supply of 80 volts capable of supplying 80 amps. Now in post #10 you say the power supply is 80 volts max and 50 amps max and then go on to imply that is has an adjustable output voltage which you set to 24 volts and that it has an adjustable current limit setting which you set to 5 amps. As you say one solenoid consumes 1.5 amps then two in parallel should consume 3 amps. IF ALL THE INFORMATION ABOVE IS CORRECT then the current limit circuit in the power supply is faulty. Can you post the manual on the power supply and the datasheet on the solenoids. If you don't have the manual on the power supply then post a picture of the front panel and back panel of the power supply. You could also try setting the current limit to 10 amps and measure the voltage and current to the solenoid using an external meter to the ones on the power supply. (As you now say it is an adjustable power supply I would expect it to have meters to display current and voltage.)

Les.
 

Yaakov

Joined Jan 27, 2019
3,769
izzarasul, You have changed your story from post #1. In post #1 you say you are using a power supply of 80 volts capable of supplying 80 amps. Now in post #10 you say the power supply is 80 volts max and 50 amps max and then go on to imply that is has an adjustable output voltage which you set to 24 volts and that it has an adjustable current limit setting which you set to 5 amps. As you say one solenoid consumes 1.5 amps then two in parallel should consume 3 amps. IF ALL THE INFORMATION ABOVE IS CORRECT then the current limit circuit in the power supply is faulty. Can you post the manual on the power supply and the datasheet on the solenoids. If you don't have the manual on the power supply then post a picture of the front panel and back panel of the power supply. You could also try setting the current limit to 10 amps and measure the voltage and current to the solenoid using an external meter to the ones on the power supply. (As you now say it is an adjustable power supply I would expect it to have meters to display current and voltage.)

Les.
80V @ 50A is still 4000W, how is this thing powered? Not even a 30A 120V circuit would handle it, is it on a 220V circuit? I am skeptical.
 

MisterBill2

Joined Jan 23, 2018
9,908
OK, now I am taking a guess that the supply is a bit like one that I have, which I got really cheap because "it did not work" Those supplies have an adjustable current limit and an adjustable voltage limit and both of those must be set to a high enough value to allow the supply to work. That is probably the source of the problem. READ AND UNDERSTAND THE INSTRUCTION BOOK!!!
IT DOES NOT MATTER AT ALL to the question asked as to what the maximum ratings of the supply are. If the supply is set to 24 volts that is all that matters. It shuts off because the current limit is not set high enough, just like my supply. The difference is that on my supply the top ends are 50 volts at 50 amps, which is why it pugs into a 240 volt 20 amp outlet.
 
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