# Delay Relay - Need advice.

Joined Jul 13, 2021
24
How about an alternative to the time delay, which would be a mechanically operated switch to release the solenoid after the hoist has lowered that 50mm distance, (about 2 inches.) It seems that some sort of mechanical switch trigger could be arranged that would be able to release it .And one thing is that if the hoist is stopped and then started again that noisy solenoid will operate every time. So a mechanically operated switch may be a better idea. AND the circuit will be much simpler.
I had thought of that and yes I will go down that path if this other system doesnt work satisfactorily, it will take a bit of setting up though not much room left.

Joined Jul 13, 2021
24
Wouldn't it be simplest to just stick a cap with a bleed resistor in series? If you know the make and break voltage of the relay, the math ain't hard.
Mikewax, sorry you lost me at bleed resistor, I have zip knowledge of electronics apart from basics,

#### MisterBill2

Joined Jan 23, 2018
14,261
Wouldn't it be simplest to just stick a cap with a bleed resistor in series? If you know the make and break voltage of the relay, the math ain't hard.
Certainly a series capacitor would work and have the advantage of not reseting instantly.

#### mikewax

Joined Apr 11, 2016
184
I have zip knowledge of electronics
this circuit will do it. Press and hold the switch, current will flow for a few seconds, depending on the value of the capacitor and the resistance of the coil. The cap will charge until it reaches 12V at which point the current through the cap will stop. At the same time, a tiny amount of current will flow through the resistor too and will keep flowing until you release the switch. Then, the charge in the cap will flow very slowly through the resistor until the cap is discharged, ready to go again.
It's quick and crude but will do the job. Dunno why nobody mentioned this earlier.

Joined Jul 13, 2021
24
View attachment 245423this circuit will do it. Press and hold the switch, current will flow for a few seconds, depending on the value of the capacitor and the resistance of the coil. The cap will charge until it reaches 12V at which point the current through the cap will stop. At the same time, a tiny amount of current will flow through the resistor too and will keep flowing until you release the switch. Then, the charge in the cap will flow very slowly through the resistor until the cap is discharged, ready to go again.
It's quick and crude but will do the job. Dunno why nobody mentioned this earlier.
Thanks for the design, looks simple enough.
If the relay fails I will give this a go. ( I have already purchased a relay thru Lazada here in Thailand.)

#### AlbertHall

Joined Jun 4, 2014
12,202
View attachment 245423this circuit will do it. Press and hold the switch, current will flow for a few seconds, depending on the value of the capacitor and the resistance of the coil. The cap will charge until it reaches 12V at which point the current through the cap will stop. At the same time, a tiny amount of current will flow through the resistor too and will keep flowing until you release the switch. Then, the charge in the cap will flow very slowly through the resistor until the cap is discharged, ready to go again.
It's quick and crude but will do the job. Dunno why nobody mentioned this earlier.

I fear that it wil need a very large capacitor to keep the relay energised for two seconds using a low voltage relay (12V) as it will have a low resistance coil.

#### mikewax

Joined Apr 11, 2016
184
If the relay fails I will give this a go. ( I have already purchased a relay thru Lazada here in Thailand.)
yeah it's more for anyone else who might find this conversation.

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#### mikewax

Joined Apr 11, 2016
184
I fear that it wil need a very large capacitor to keep the relay energised for two seconds using a low voltage relay (12V) as it will have a low resistance coil.
yeah you'll really have to do the math first and get a Hi-R coil and a mF cap, but they're cheap enough at digikey like <\$2

Joined Jul 13, 2021
24
I have recieved the relay (finally) and would like some direction for the connections.
It is a H3YN-2 withs a DIN Rail mounting socket for HPCO Relay.

The purpose of the relay is to activate a 220 volt solenoid for 2 seconds, the switching power is 12 volt and the switched power is 220 volt.
The 12 volt power remains while the lift 'down' button is held (approx 2 mins)

I assume that the 12 volt switching will go to terminals 13 & 14
The 220 volt positive & Negative will go to terminals 9 & 12
The N/O selection will go to terminals 5 & 8.

On the side of the relay there a 4 switches:
The upper 2 determines the time delay, I have chosen 10 sec.
the lower 2 determine the mode:
Which mode do I need:
ON-delay
Interval
Flicker OFF-start
Flicker ON-start

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