Problem with IN4004 diode in a fire fighting system control panel

[ahmed tolba]

in4004 diode

Hi,
I am working with a fire fighting system control panel, and I have a problem in the panel output.
the out should be connected to a solenoid to control opening the extinguisher as in picture

the diode is connected to prevent transients made by solenoid coil from entering cct.
PROBLEM IS : this diode brings the 24 output to (only 0.6 volts) which is not enough to operate the solenoid????
I can remove this diode ....but what about coil spikes??? need your advise.
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[GSM Man]

diode in4004

If the diode is connected as shown in your schematic is will be reserved biased and should not be conducting. Therefore it shouldn't be dropping the voltage to 0.6v. However, if it is reversed (cathode to negative side of supply) it will be forward-biased and will drop the voltage to around 0.6V. I would check the polarity of the diode and your supply connections.

 

[ahmed tolba]

in4004

but I am sure of the diode polarity and also the sourse,
I wonder if this type of diodes has low break down voltage so it conducts in the reverse direction???

 

[elrayes]

dioda in4004

try to test the diode to check from diode polarity.
try to replace the diode with another one from the same type or replace it with another diode like 1N4007 or 1N4818.

 

[nandhu015]

diode voltage in4004

Possible not due to some other thing and not the diode
Check out the other things

Nandhu

 

[Js_Ong]

in 4004

Ahmed,

Have you manually check for your solenoid? Is it work when you plug to 24V by manually? Your problem seems like the solenoid already has opened circuit.