# Needs to Start Solenoid from Pulse generated by end of timer

#### Kkyy

Joined Dec 25, 2021
10

#### Kkyy

Joined Dec 25, 2021
10
At Timer circuit end generate 0.5-1 v pulse use to drive(on for 1sec) relay solenoid valve. Design external circuit for generate short pulse from continue on pulse train .
Any recommendations achieve this! Thanks

#### eetech00

Joined Jun 8, 2013
3,418
At Timer circuit end generate 0.5-1 v pulse use to drive(on for 1sec) relay solenoid valve. Design external circuit for generate short pulse from continue on pulse train .
Any recommendations achieve this! Thanks
translation:

"I'd like a circuit that will generate a 1v pulse, for 1 second, to energize a solenoid valve"

Is this correct?

#### Jon Chandler

Joined Jun 12, 2008
607
If the effort put into asking the question is near zero, the effort to answer the question should be expected to be the same.

#### Kkyy

Joined Dec 25, 2021
10
translation:

"I'd like a circuit that will generate a 1v pulse, for 1 second, to energize a solenoid valve"

Is this correct?
Yes, exactly circuit takes input from timer pins at the end of timer.and just start solenoid for 1sec.

#### eetech00

Joined Jun 8, 2013
3,418
Yes, exactly circuit takes input from timer pins at the end of timer.and just start solenoid for 1sec.
What type of signal will trigger the circuit?

#### Kkyy

Joined Dec 25, 2021
10
translation:

"I'd like a circuit that will generate a 1v pulse, for 1 second, to energize a solenoid valve"

Is this correct?
Yes, exactly circuit takes input from timer pins at the end of timer.and just start solenoid for 1sec.
What type of signal will trigger the circuit?
Timer one pins generate 0.50-1.5v pulse to zero at end timer 0.0 use this for trigger transistor connected 12 v relay.

#### Kkyy

Joined Dec 25, 2021
10
I'm a little bit confused, is this thread a continuation of the one you posted in the link? If so what happened with that? From what I read you and eetech00 were working on a circuit and it just ended kind of hanging and that was 6 months ago.
Yah similar kind of fuction but he use battery and remove relay from coil and connect direct h bridge.but i want just last fall edge(state) detection of timer High to Low and trigger further circuit pulse of solenoid coil trigger for 1 sec and off.

#### sghioto

Joined Dec 31, 2017
4,162
I apologize for misreading the link, I thought you were the TS in that link. So starting over, this output from the timer pin does it vary? Why .5 to 1.5 volts? In post #9 it says use to trigger transistor connected to relay but now you are saying to pulse solenoid for 1 second. So are you saying pulse the transistor-relay circuit for 1 second and the contacts of the relay will pulse the solenoid?

#### Kkyy

Joined Dec 25, 2021
10
Sorry for bit
I apologize for misreading the link, I thought you were the TS in that link. So starting over, this output from the timer pin does it vary? Why .5 to 1.5 volts? In post #9 it says use to trigger transistor connected to relay but now you are saying to pulse solenoid for 1 second. So are you saying pulse the transistor-relay circuit for 1 second and the contacts of the relay will pulse the solenoid?
Sorry for bit confusion.Actually Timer count down 30 min to zero then end pins voltage pulse 0.5-1.5 become zero . afterwards design such circuit which detects timer end and generate Pulse to trigger solenoid through transistor-relay circuit (not directly) for 1 sec punch. Please suggest Solution.

#### sghioto

Joined Dec 31, 2017
4,162
Actually Timer count down 30 min to zero then end pins voltage pulse 0.5-1.5 become zero
Still not sure what this .5 to 1.5 pulse is. When the timer is counting down are you saying there is a .5 to 1.5 volt dc voltage on the pin? Then when the timer is at zero the voltage on that pin drops to 0 volts, correct?

#### Kkyy

Joined Dec 25, 2021
10
Still not sure what this .5 to 1.5 pulse is. When the timer is counting down are you saying there is a .5 to 1.5 volt dc voltage on the pin? Then when the timer is at zero the voltage on that pin drops to 0 volts, correct?
Right

#### Tonyr1084

Joined Sep 24, 2015
7,353
15 posts in and still not clear. There's 0.5 to 1.5 volts present while the timer is operating? Then when it drops to zero you want a 1 second pulse to a solenoid? Assuming this is what you want, using a transistor to control the solenoid, to my knowledge (small as it is) a transistor needs a higher voltage - actually sufficient current - to switch it into saturation. This situation sounds more like a need for an amplifier with some off-set DC voltage to aid in triggering the solenoid. Again, I'm limited on knowledge in this area - so others will likely correct me quickly if that's the case.

I have more questions: From where is this 1.5V coming from? Your timer - is it just a switched timer? Or is it a timed power source? I'm not fully convinced we're discussing things correctly. This half to one and a half volts could be an aberration of a meter not set properly. I'm confident we can find an answer to your question, but we need to fully understand it.

#### sghioto

Joined Dec 31, 2017
4,162

Last edited:

#### eetech00

Joined Jun 8, 2013
3,418
Yes, exactly circuit takes input from timer pins at the end of timer.and just start solenoid for 1sec.

Timer one pins generate 0.50-1.5v pulse to zero at end timer 0.0 use this for trigger transistor connected 12 v relay.
Is the solenoid a single coil latching solenoid that requires a polarity change to change its state?