Contraves NC414 Drive Transistors???

[slick_ride]

I have one bad servo drive for a Bridgeport series 1 R2E3. It has Contraves NC400 drives and the model number is A1520. I believe that it has 6 bad transistors. Four around the perimeter of the heat sink and two that are on the board itself. They are four different parts. I looked at the Contraves amplifier manual online and it does not give the data specifics of the transistors (manufactured by CSR and General Electric). Digikey and Newark pulled up zero hits when I typed in the code on the units. I was hoping someone may be able to help. Here is the info.

1. Q0023-B (EP1685A)(980 8302)
2. Q0024-C (EP1686A)(8238)
3. Q0036 (H8139 or H8142)(RCA)
4. D44Q3 (GE)

Thanks,
Dan

[Jonp]

I've ran into the same problem with these amps, seems as though they were manufactured with house numbered transistors. I am hoping that sooner or later I'll run across a repaired one that has some common marked transistors. If anyone has any info I'm also interested, thanks , Jon P.

[NC Cams]

the D44Q3 is an ECG51. Vce is 400 and it can carry 4 amps. It is a silicon NPN that should be easy to get from a number of sources. TO-220 package

The ECG manual shows you how to determine/identify transistors once you pull them out of circuit. If these are in an H bridge it can be a bit easier. THe two transistor in the 'top" legs tned to be PNP's. the lower legs tend to be NPN's.

If you know the voltage of the P/s, you can generally figure out what to look for in a Vce rating. Again, the ECG book can be quite helpful in this regard.

A higher voltage rating and current rating for a given package should NOT be a problem. In fact, higher current ratings would be beneficial to durability.

If he circuit has schottky diodes or any diode protecting the transistors, replace then too. IF thes pop, they can let flyback voltages to take out the transistors quite easily.

Finally, have you contacted COntraves???

[Goslowjimbo]

jonp, I believe the output transistors can be replaced with a TIP34C and TIP33C. They come in the TO-218C case like the NC400 transistors, or a TO-247 case, which is an improvement over the TO-218C. I haven't tried this yet, but will soon. I would recommend always replacing them in pairs, as the specs will probably not be exactly the same as the original Q0023 and Q0024.

Sorry this is so much later.

[suzukirmz]

Q0023 - Name Brand Replacements - TRANSISTOR