[whitewittock]

I switched on my X2 last week and the motor started briefly then suddenly slowed down and died. The orange fault light was lit. The fuse was blown and the next fuse I inserted blew as well. I traced the problem to the Bridge Rectifier, and swapped it with a like for like piece.

Now when I switch on my X2 I hear a familiar 'click', the fuse doesn't blow, and the orange fault light is not lit, but the motor doesn't start! I could swap out every part on the board for less than it costs to replace, question is where to start?!

[Dano523]

Pick a direction, either from the 110ac in, or from the 90V DC out with the volume pot wide open, and start tracing.

Could be a possibility of anything, even down to a blow pot.

http://www.hossmachine.info/Gerling%...viceManual.pdf


Now having said this, It may be cheaper to just replace the motor control board with a KBLC-19PM and be done with it. The KBLC-19PM have been discontinued, but show up on Ebay for under $20 from time to time. Throw in the needed resistor for around a buck, and reuse your pot if it not blown, and your a done deal for around $20 in the end.

KBLC BOARD

But the warning, the stock motor controller only puts out 90 volts, while the motor is rated at 110volts. This is done to hobble the motor so it will not blow the plastic gears. Yes, the KBLC-19PM can be back off so you don't destroy the plastic gears first time out, but kind of missing the point of going to the new board. The new board puts out 125v, and with it, brings the machine to life with a belt drive that will not melt down when you put power to the workpiece.

[SCzEngrgGroup]

By far the most common failure in those controllers is the FETs. Often it is exacerbated by the current limit and IR compensation having been very poorly adjusted at the factory.

Regards,
Ray L.

[john-100]

based on my experience with the FC250 board used on the minilathes
the FET's go short circuit blowing the fuse and sometimes the bridge rectifier


after looking at the circuit diagram for your control at --

http://www.hossmachine.info/Gerling%...viceManual.pdf

I'd first check you have a resistance of 0.33 ohms between relay RL1's common terminal "p" and the bridge rectifier + terminal

also you should have about 240V DC between the bridge rectifiers negative terminal and the PCB's terminal TB2



using a 240V 60 to 100W GLS tungsten filament bulb as a dummy load and the potentiometer fully clockwise ( or terminals P1 and P2 linked together)
you should have about 220V DC between the output terminals 1 and 2 -- normally the maximum output at terminals 1 & 2 is less than the bridge recifiers DC output

if not, either relay RL1 is not connecting the choke L1 to the PCB terminal 2
or the fet's are not switching on

when using the bulb as a load
you can connect relay RL1's terminals P(com) and S (normally open contact) together -- don't forget to remove the test link after the test

if the FETs are not being switched on
check the outputs of the two 12 V regulators are OK
****note the 7812 positive 12V regulator output is connected to the mains bridge rectifiers positive output !!!

John

PS this may help ----- speed control pcb for Clarke CL300 lathe | Model Engineer

some of the info is from my repair of a FC250 speed control -
its a cut down version of your board

[whitewittock]

Thanks for all the insight! Just look forward to some free time to do it lol. If it was the FETs/MOSFETs I wonder if that would that not blow the fuse.. KBLC board would be good if I can use a 240v transformer, but I'm still hoping this is an easy fix till proven otherwise!

[john-100]

Hi

If you are going to use a KB Electronics speed control board
I'd look for the 240v version of the control board
a 400/500W 240/110V step down transformer will be an expensive option

with the KBLC .....board you will need to add a no volt release circuit

on the original FC350JB board, two of the relays form the No Volt Release circuit that also is part of the interlock that forces you to start at minimum speed
this limits the motor start up current


if you can find the circuit diagram for both versions
it would be possible to convert a 110V board into a 240V version
the two thyristors and the three power diodes
will need changing for 800 -1000v versions and a few of the resistors etc

John

[whitewittock]

Still working on this fix and waiting for a new POT to arrive.

As a backup or plan B, would any cheap chinese 230vDC 350w+ motor speed controller like these work? Not too worried about emergency stop safety features, minimum speed start etc, just want to get this spinning again!

2000W 220V High Power SCR Electronic Voltage Regulator Dimming Thermost Motor Speed Control Controller

http://www.quasarelectronics.co.uk/cebek/r-9.htm

[Al_The_Man]

Personally I would not consider that unit, I only see one SS device so for DC it is pretty sure to be a SCR, which dies not give you greater DC control that a full wave bridge does.
BUT it says dimming thermostat which normally is a Triac (AC) control and it shows AC in and AC out?
Plus there is very little else (or nothing) in the way of ramp or decel and the only protection is the one fuse.
If your motor is =<1HP there is a qty of Danfoss units on ebay for $30.00, similar in design to the KB/Baldor.
He may ship to UK?
Al.

[whitewittock]

Personally I would not consider that unit, I only see one SS device so for DC it is pretty sure to be a SCR, which dies not give you greater DC control that a full wave bridge does.
BUT it says dimming thermostat which normally is a Triac (AC) control and it shows AC in and AC out?
Plus there is very little else (or nothing) in the way of ramp or decel and the only protection is the one fuse.
If your motor is =<1HP there is a qty of Danfoss units on ebay for $30.00, similar in design to the KB/Baldor.
He may ship to UK?
Al.

I remembered after posting that it has to be DC out, -the board does look suspicously small!
will need to fetch my glossary for SS, SCR?

Maybe these are the right thing, the X2 motor is 4/5 HP, 230vdc 350w. If you have a link to what you saw on ebay please let me know.
AC110/220V Input 2A/3A/4A/5A 1000W SCR DC Motor Speed Controller Driver Adjuster | eBay

http://www.ebay.co.uk/itm/HX-PWM-AC2...item1c281fef08