Diode identification.

Thread Starter

shteii01

Joined Feb 19, 2010
4,644
Help please.

Diode, black cylindrical body, white/gray/silver stripe on the cathode end. On the body: J-4. What model or can someone link datasheet for it, please.
 

ian field

Joined Oct 27, 2012
6,536
Help please.

Diode, black cylindrical body, white/gray/silver stripe on the cathode end. On the body: J-4. What model or can someone link datasheet for it, please.
With only that to go on, you might stand a better chance by getting hold of a schematic for what its out of.

Assuming its not blown, a Vf reading from a DMM diode check function will tell you a fair bit - if it is blown, look for another just like it and measure that.
 

Thread Starter

shteii01

Joined Feb 19, 2010
4,644
With only that to go on, you might stand a better chance by getting hold of a schematic for what its out of.

Assuming its not blown, a Vf reading from a DMM diode check function will tell you a fair bit - if it is blown, look for another just like it and measure that.
Hm, I did not think it would be this complex.

Ok. Here is the rest of the story.
it comes from a General Electric Can Opener, Catalog Number D2EC60, Maximum 1.3 A, 120 volts AC, 50-60 Hz. The electric motor works. But the schematic is really simple, two prong wall plug, one wire from the "left" prong goes to the electric motor (red), another wire comes out of the motor (yellow) and goes to one side of the ON/Off witch, from the other side of the ON/OFF switch I have this diode and diode goes to the "right" prong.
Left Prong->motor->switch->diode->Right Prong
As you can see once I plug the two prong plug into the wall, the circuit is complete.

The best I can figure out the diode forms half wave rectifier.
 

ian field

Joined Oct 27, 2012
6,536
Hm, I did not think it would be this complex.

Ok. Here is the rest of the story.
it comes from a General Electric Can Opener, Catalog Number D2EC60, Maximum 1.3 A, 120 volts AC, 50-60 Hz. The electric motor works. But the schematic is really simple, two prong wall plug, one wire from the "left" prong goes to the electric motor (red), another wire comes out of the motor (yellow) and goes to one side of the ON/Off witch, from the other side of the ON/OFF switch I have this diode and diode goes to the "right" prong.
Left Prong->motor->switch->diode->Right Prong
As you can see once I plug the two prong plug into the wall, the circuit is complete.

The best I can figure out the diode forms half wave rectifier.
Doesn't sound like its anything fancy speed wise, but the current would be too much for a 1N400x series, as long as you're sure its used as a half wave rectifier, you could try a 1N5408.

You need to double check its not a transient suppressor directly across the mains before sticking a regular diode in there!
 

studiot

Joined Nov 9, 2007
4,998
Are you sure it's not a thermal fuse/varistor?

Many portable appliances have these and they look just like diodes.
 

THE_RB

Joined Feb 11, 2008
5,438
Probably a 4 amp mains rated silicon diode.

A 1N5408 is a good call, and at 3 amps rated should be pretty close to the task. Your motor likely draws less than that.
 

ian field

Joined Oct 27, 2012
6,536
Are you sure it's not a thermal fuse/varistor?

Many portable appliances have these and they look just like diodes.
AC devices don't usually have a silver band at one end.

Often I find DB3 diacs in scrap CFLs, they usually have the same case style as the 1N4007/FR107 diodes usually there too. Quite interesting devices to play with, the lack of a polarity band makes them easy to pick out.
 
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