3000W Chinese Gensets Info.

pritch272 wrote:
ok Prof- Here's the C46540 schematic, I see that it has a transition, does that imply it has over voltage protection? No, it does not as it's only 2 wires and a ground, per your earlier posting which I just re-read.

I do wonder how quick the EMS-HW30C can react to the 192 VAC if the AVR does fail ...

Yep, you answered your own question. The C46540 does not have the OVPM.

I would expect the EMS-HW30C would open the supply circuit fast enough to prevent damage. It would not shut down the generator. But, the HW30C is a $300.00 device, the KILLAVOLT is $39.95 and surge protectors with Metal Oxide Varistors (MOVs) are less than $10.00. Thus, there is now an affordable over voltage protection device commercially available.

At the bottom of this text is a photo of the device identified as the two wire "Transition" in the schematic. Why it is named transition is a mystery to me.

This is a photo of the de-potted transition.



Anyway, the device receives power from the ignition coil. When the yellow wire to the transition is touched to ground, it latches and stays latched, grounding the coil so there is no spark, until the engine is completely off. The latch is a simple single transistor circuit with an electrolytic capacitor. The charge in the capacitor holds the latch closed to ground even after the supply voltage is removed. Every Chinese synchronous generator of this type that has a low oil shutdown feature - no matter what the wattage or who makes it - uses an identical transition. The Chinese transition can be used as a replacement on Coleman Powermate, etc. - even my 20+ year old Kawasaki 1400. The technology has been around a long time.

Without the device the low oil float switch would probably not shut down the engine. It would just intermittently ground the coil making the engine sputter.

With the transition, you can have a simple spring loaded normally open push button switch to kill the engine. Simply push the button once, the transition latches and the engine shuts down.

With the KILLAVOLT plugged in, as soon as it senses an over voltage a ground signal is sent to the transition. It immediately latches and the engine shuts off.

When CPE designed the OVPM they made the transition part of the circuit, eliminating the silver cube shown in the photo.

I think SuperGen Products will provide the silver transition for anyone ordering the KILLAVOLT that has a generator that DOES NOT have the device as OEM equipment.

BTW - the generator I have shown in the photos is my experimentation generator. I acquired it used after a thousand or more hours of service and have disassembled and reassembled most every part on it several times. Amazingly, it still works :C