I'm not actually popping the scr..it's getting hot and blowing the solder off the pins on back of board..replaced the one that smoked in reverse.switched motor wiring back..ran 5 seconds then blew solder off the other one..loud pop.kicks house breaker when it blows..any ideas on which way to go..thanks Phil
What type of motor are you using here? Let's see it
ps You tested all 5 semiconductors with the jig? Did you test the SCRs for tab to anode continuity?
If you are blowing the house breaker you still have a dead short across the power line
I'm still thinking those are NOT isolated tab SCRs and you are putting a short across the power line as soon as you bolt them to the panel
It would be good if you could plug into a GFI protected outlet to test these controllers, it would trip much more quickly and there would be less damage.
Here is what I would do: Get another unit ready with tested semiconductors. Before you mount the SCRs to the panel, measure the resistance with an ohmmeter across 1 and 4 of the terminal block. Then measure again after you mount them to the panel. If you get a different (lower) reading DON'T plug it in.
The SCRs will need insulating hardware, or you will need to replace with iso-tab types. (easier)
The scr is not grounded to cover.bolts are nylon.made tabs out of plastic coffee can lid.scr has continuity on outside wires but not to center wire .tab to center wire .no continuity.the semi conductors pass current one direction but not the other.the motor is the Baldor gear motor I used on my vSd..1/7 hp I think..will wire up a gfi outlet b fore plugging up again..thanks very much for your help..
You did use a jig to test the SCRs? Continuity between outside leads sounds wrong. Shorted gate problem maybe- Gotta use the jig to be sure
sounds like you're doing everything right so far- coffee can lid plastic isn't the best material for that though. OK temporarily
Even if the controller was firing both SCRs at the same time the worst that would happen is the motor would run full speed, so I'm not sure what the problem is
Verify for me: You hook up SCR to jig, lamp is off. Touch wire from gate to middle pin (anode) lamp lights and stays lit until you remove 12 volt supply?
Any other behavior means SCR bad. (no light, or light on without touching gate)
Used a 10v dc charger.automotive test light hooked on one wire..other wire a probe..all the scr I've tested so far pass current on two outside wires..on two bulb is dimmer when switching wires around..on two brightness same
Motor is 90v..1.53 amp..field on control is 50 v..arm is 90v..solder at scr blows out in a spray of dots..also black smudge..but looking at scr it looks no different.do I need to get a few scr's..if where.i looked on eBay but don't see any with same number..thanks
Phil: You have bad SCRs. The only correct result is as I said above. They should be off initially then latch on and stay on when you tickle the gate. You should pull all of them out and test. You can't test them easily with an ohmmeter. Can't test reliably unless removed from board.
Also to test the big diodes you need to remove them or at least lift one end from the board, otherwise you may get confusing readings in circuit. You can test those with an ohmmeter.
I'll get back to you with some part #s for replacements
Phil: Littlefuse brand S6010LTP available from Newark electronics about 1$ each +shipping
or Littlefuse brand S8020LTP available from Mouser electronics about 2$ each + shipping
these are both isolated types, first one is 600 volt, 10 amp. Second one is 800 volt, 20 amp.
either one will work fine with a 1/2 hp motor which is the max for those controllers.
For the big diodes you can use this 10A10 part:
For that SCR jig test you must use a steady dc source like a battery or a filtered dc supply. A battery charger may not give the latching behavior you want to see.
Just so you know. By tickle I mean connect wire briefly from gate to anode- you follow?SCRs are latching devices, they only turn off by removing the power or reversing the polarity of the power. That's how they control ac because ac reverses 60 times per second
Sure Phil you can use a cordless drill battery, a 12 volt battery and bulb would be ideal. Even a 9 v Makita battery would work. Long as it lights up even half brightness it
will work for doing the test. Once you see the "latching" action you'll know what I've been talking about- however, prepare to be disappointed since all your SCRs might be
burned out. Let's hope you can find at least two good ones.
ps motorcycle battery would work too, or even some flashlight batteries in series.
Not sure I'm doing this right..using clip I'm connecting a outside wire to middle wire..all 3 wires light test light,.of course the two clipped together would..couple scr are dimmer on separate wire..I'm thinking not doing it correctly
Unsoldered a scr off a treadmill panel board..with power to tab all wires light up..one is dimmer than other 2..power to any wire lights up all 3..but with ohm meter no continuity from tab to center wire
Found site on how to test scr with meter..set it on 2000 M..any lower read OL...did 3...040 neg on A..111!pos on c..short g to A 10...remove ...A went to 108...2nd...same order. 035....119.....short g to a. 010 remove went. OL...3rd almost same reading...any good?? Or bad??hope 1 reads good .if so can test all until find 2...mark..thanks for part numbers..AND you time..
I don't understand your meter readings, but if you think you have a good one, check it with the battery and bulb. If it doesn't pass the latch test it's still bad.
I've never gotten good results trying to test scrs with a meter.
I'm going to study your directions again them try to test with bulb..Mark at Galco industrial electronics sent me some pictures of factory directions for 2301 and 2302 control.tthink it was good of him to go in warehouse and dig thru old paperwork..of course you were correct.1 and 4 incoming power..1 and 2 motor shunt field..2 and 3 motor arm..is my Baldor shunt wound?? Thanks Phil
On three scr did light bulb test .put negative on center wire ..positive with bulb touching either wire to left or right of center no light..removed scr from a mc2100 control.did same test .it lit up..gonna test until I get 2..I hope..if not going to order some. Thanks Phil
I don't think the Baldor has a field; green is probably ground.
So when you tested the scr from the mc2100 the light came on and stayed on when you removed the wire from the gate? If so that's a successful test.
I'm going on memory on this and this drive is a very old drive. Which brings up a point electrics age capacitors dry out or short out. Be mind full of this when you purchase old electronics even if its free it may not be worth the price.
As I remember these drives could be operated on 115 or 208/230 single phase. The 4 terminals I believe were used to set the operating voltage of the drive. This was accomplished by switching jumpers on the primary of the small power supply transformer for the control circuits. So these terminals are not the AC input or the DC output . It was common 30 years ago on small enclosed DC drives to connect the power leads directly to the fuse block or the power switch. The Armature was often connected directly to the reversing switch. if there is no terminal marked L1 /L2 or terminals marked A1/A2 or A-/A+ the power and DC output was most likely connected as described above.
Again I am relying on my memory and could be wrong.
if you use Google search the manual will show up but my virus checker lit up like a Christmas tree when I tried to down it. Again from memory some of the Fincor DC drives were build by Dart controls which is still in business they may be able to help with a manual.
Mark has been walking me through testing scr's and trouble shooting..scr's were bad.have one up and running for now..couldn't find manual for a 2301.found one for 2330 but totally different..called Galco ind. electronics.mark(a different mark)went in warehouse and dug out a manual and emailed to me..lots of info in the 4 pages..Thanks