G201-IP

Hi,

I have breadboarded a protection circuit for the G201. It protects
against:

1) Shorting any or all motor wires to ground.
2) Shorting any motor phase to phase.
3) Miss-phased motors (series or parallel).
4) Miss-connected motors.
5) Internal motor winding shorts (serial-killer motors).
6) Motor connects/disconnects while under power.
7) Motor winding short to motor case.
8) Unused 6-wire motor leads touching/shorting anywhere.

These are the most common drive failure problems (>95%) that we see
for return/repair.

The circuit works internally on the "DISABLE" input (term. #7) of the
drive. Any of these faults would latch it low (disable). It would
then require a recycling of the power supply to clear the fault.
The "Fault" indication would be a "0" on the "DISABLE" terminal.

The "IP" in G201-IP stands for "current protect", or as a cruel
individual here pointed out, it can also read "Idiot Protect".

This circuit (about 20 additional components to the existing 136)
would require a major revision (REV-8). Of course it would be 100%
compatible, pinout, function and form, with all previous drives.

What I am throwing out to the group here is:

(1) Is it worth the effort to do this?
(2) Is it worth a $15 premium to do have this protection? That is the
all-up cost of the additional parts.

We will continue to produce the G201 regardless if there is or is not
a G201-IP. It will not in any way supplant it.

The G201-IP might be useful for those that are using the drive for
the first time and want a little extra margin against Mr. Murphy and
his Law. Later, after everything has settled out, stock G201s would
serve as well. Others that are a little more tense/prudent may wish
to have it as protection against Mr. Murphy should he call uninvited
at a later time.

If I'm going to do this, my schedule has it for the end of the first
quarter. What I'm looking for is feedback if this is wanted/needed.

Thanks.

Mariss