[Newbie] G0704 Over Heating, No Start

Called Grizzly. Primary C/B is on back order till May 26. Searching for an alternative.
 
If the original is the Chinese knock off of the KB board, most are, the KB is a major improvement!
 
I had similar experiences on a ZX45V mill, which is the same as the Grizzly G0762 but with a Delta VFD. I did the following changes:

1. The VFD was overheating as was evident by the hot "electronic" smell. The wire trunking above and below the VFD closed off the cooling channel and internal VFD fan thus preventing any air to flow over the heat-sinks. I removed some of the tabs on the trunking to allow for better cooling.
2. The panel was equipped with two ventilation holes that were covered with filter covers. These were so dense that no natural air flow happened with a resulting increase in the ambient temperature inside the box. VFD's rapidly derate with increase of ambient temperature. I equipped the bottom ventilation hole with a small computer type cooling fan, which forced the hot air from the enclosure. You might want to consider a cooling van for your enclosure. Its capacity needs to be just big enough to cause the air inside the enclosure to be replaced a number of times per minute. This can be easily achieved with an old PC fan.
3. I equipped the 5Volt power supply of the digital speed indicator with additional smoothing capacitors and inductors to prevent interferences from the motor start surges.
4. Lastly, I upped the circuit breaker on the low voltage side from 2 Amp to 3 Amp to prevent occasional trips due to inrush current on the contactors.

Not all these items would help you but can be used by others with similar problems. However I recommend you seriously consider the fan modification and ensure that all heatsinks are clear of obstructions.
 
I will be receiving the KBIC-125 a Heatsink and a KB Electronics KB-9849 AC Line and Motor Armature Fuse Kit for KBIC model drives Thursday evening. Since I have no experience R&R'ing these components. It'll be a small challenge.

If anyone can provide me with some guidance, it would be greatly appreciated.

I like the idea of a fan mod.

Thanks

George
 
I've done a lot of the KBIC 240v (UK Mains), one thing to know is the speed control pot isn't isolated so it needs careful attention to insulating the terminals and a PLASTIC knob for safety!

If you're bolting the heatsink through a panel then to the speed control board (ground the box!) use either thermal compound or thermal silicone sheet between both and the case for best heat transfer.

The fuses should be accessible if possible (panel fuse holders are good) and in the line wire for the mains in, A+ to the motor.

If using a reversing switch, plan for one which also cuts the supply BEFORE reversing the motor, it'll improve reliability.
Hope that helps.
 
Making Chips!

Replaced the Chinese Controller with the KBIC-125 to see how things would go. I added the Combo-Fuse-Kit also. Runs well. However, I will need to adjust the RPM's.


Thanks for all of the helpful suggestions.
 
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