John Neiswanger wrote:

> Well, more information and some more confusion on my part.  I checked the
> continuity and it was still good so I opened the unit and looked inside.
> There is no discoloration, melted cases on the relay or any appearance of
> a cracked solder joint that I could see.  It does appear that someone had
> been in there before as the input fuseholder that is mounted by the power
> cord is not connected into the circuit and there is a soldered in fuse in
> the line.

That would be a factory modification.  The very earliest production units had 
the AC input fuse in a externally-accessible sealed holder, however, we very 
quickly did away with the fuse holder and went to a non-user-replacable fuse 
soldered to the board.  (The issue is that the input fuse should never open 
except in the event of catastrophic internal failure, but when mounted in a 
sealed holder, the body of which is in a 70C ambient while the charger is 
operating, there were instances of the fuse opening simply due to operating at 
an excessively high temperature.)

> There is also a Belden cable (1 twisted pair, shielded) that comes out by
> the DC output cord.  It is taped and insulated on the exposed end and it
> connects to the main circuit board close by the DC relay or possibly to
> the control board down close to the main circuit board.  There is also a
> sticker on the mounting foot on the front (AC) side of the unit that
> states "slave address 37".

AHA!  The Tropica you have borrowed used to be Steve Bischoff's.  This is an 
older charger that has been modified (by Delta-Q) to support serial 
communication.  Assuming the person you borrowed the car from got everything 
from Steve, he should have the interface device to go between a PC and that 
comms connection.

> In any case after having a look around, I re-assembled it and took it back
> over to the car and connected it to the battery pack to see if there was
> any change.  It still came up with the "internal error" code so I tried it
> without the battery connected and it showed a different code of 2 flashes
> indicating that the voltage was low.  So it isn't brain dead.

The charger will indicate fault code #2 (low DC voltage) when no battery is 
connected.

Fault #6 will only appear after the charger detects a valid battery voltage and 
decides to try closing the DC output relay to connect to the battery (since it 
is at this time that it performs checks to try to confirm that the relay 
contacts close when commanded).

> I then cycled through the profiles and went ahead and set it for #5 as
> I felt I didn't have anything to lose at that point.  At that point I
> tried connecting it back to the battery pack and it powered up and
> started charging at the second level on the ammeter LEDs.  I checked
> the voltage on the output connections and it was pushing 88 volts into
> the batteries.  Their resting voltage just before was 76.8 volts
> A short while later I noticed the green LED flashing and shortly it
> went to steady on.  Before I left tonight I un-plugged it and then
> plugged it back in 30 seconds later and it showed it was charging
> again.  I'll check it tomorrow to see if it is back at full charge
> again.

Unexpected, but good news! ;^>

That the fault went away after changing the algorithm to one more suitable for 
the battery suggests that a fault (such as DC over-voltage, or DC 
under-current) was occurring as a result of the battery responding in an 
unexpected way to the inappropriate algorithm, and when the charger opened the 
output relay in response, it was unable to confirm that the contacts had opened 
(so, indicated fault #6 to alert you to the possibility of welded contacts).

> Doea anyone have a suggestion for a suitable charger for this battery pack
> that I can pass on to the owner?  Preferably one that can use either 120V
> or 230V input.

If the present owner got everything from Steve, then he should have two of 
these 72V chargers already.  Check with him to confirm, and if he does have a 
second one, set it to algorithm #5 as well.

The pair will deliver at least 24A into the pack, which is probably enough to 
do the job.

Cheers,

Roger.

_______________________________________________
UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
http://lists.evdl.org/listinfo.cgi/ev-evdl.org
For EV drag racing discussion, please use NEDRA 
(http://groups.yahoo.com/group/NEDRA)

Reply via email to