Briggeport Gecko wiring - battery bulb test etc...
Posted by
theokspindoctor
on 2004-08-17 22:24:42 UTC
I appreciate all the input so far, but little progress tonight.
Jon's suggestions re listening to the output from the GEcko step
terminal is a future test as well as removing the resistor if that
is safe. I did remove the resistor tonight and it did not help the
max stall speed of 20 ipm. I can't easily remove the 2:1 gear
reduction but it seems possible, hopefully I will not have to resort
to that modification. I am using 75 volt power, Also, the z axis
has very little load and stalls at the same speed so I don't think
load is the problem.
Les' suggestion with battery bulb test seems equivocal. The first
test with 12v battery with 12v bulb shows the 4 windings as I
originally thought with light bulb lighting in the following pattern
7-4
8-2
3-5
1-6
This winding pattern is as it is described in the manual and there
was no shorting found. However when I wired the Gecko in the pattern
8-2 to phase A and 1-6 to phase B it burned the drive even though 8-
2 and 1-6 are a circuit as demonstrated by the battery light test
and voltmeter tests. It still does not make sense that the axis
motor will run with Gecko phase A+ to 1 and A- to 2 with B+ to 8 and
B- to 6. This wiring setup seems to cross windings as should
according to the discussion earlier burn the Gecko.
With the battery connected across 7-4 the bulb lights and with
second lead across 8-2 there is an audible click and slight movement
but I can then turn the motor by hand with resistance. Then with
the second lead across 3-5 or 1-6 there is a slight movement again
and I cannot turn the motor by hand. Reversing the lead never seems
to make much difference in any test. Similar findings with 8-2
against 3-5 and 1-6. I'm not sure how to interpret these findings.
Since the axes were moving with the way the installer had it wired,
according to Jon, there is no need to continue to fool but just
leave it as he had it, since it moves and changing to other windings
will not help.
The Bridgeport manual shows the Sigma Windings. It has a wire
coming for instance from a small circle labelled 8 and continues
with a coil shape to a circle labelled 2. I assume that represents
one winding.
Mariss' drawings in the Gecko white paper show parallel and series
wirings of an 8 wire motor using all 8 terminals on the motor. He
does not show just wiring 2 of the 4 windings to the Gecko as we are
discussing doing here. He also mixes the terms series and parallel
with full and half winding. If done correctly, could I be more
successful with using all 8 terminals as he shows in the white paper
using a series or parallel configuration?
I hope Les Newell reads this and might be able to help me understand
why our machines are responding differently.
I hope we can get this all figured out for future generations of
Bridgeport fans...
thanks!
Keith Clark
Jon's suggestions re listening to the output from the GEcko step
terminal is a future test as well as removing the resistor if that
is safe. I did remove the resistor tonight and it did not help the
max stall speed of 20 ipm. I can't easily remove the 2:1 gear
reduction but it seems possible, hopefully I will not have to resort
to that modification. I am using 75 volt power, Also, the z axis
has very little load and stalls at the same speed so I don't think
load is the problem.
Les' suggestion with battery bulb test seems equivocal. The first
test with 12v battery with 12v bulb shows the 4 windings as I
originally thought with light bulb lighting in the following pattern
7-4
8-2
3-5
1-6
This winding pattern is as it is described in the manual and there
was no shorting found. However when I wired the Gecko in the pattern
8-2 to phase A and 1-6 to phase B it burned the drive even though 8-
2 and 1-6 are a circuit as demonstrated by the battery light test
and voltmeter tests. It still does not make sense that the axis
motor will run with Gecko phase A+ to 1 and A- to 2 with B+ to 8 and
B- to 6. This wiring setup seems to cross windings as should
according to the discussion earlier burn the Gecko.
With the battery connected across 7-4 the bulb lights and with
second lead across 8-2 there is an audible click and slight movement
but I can then turn the motor by hand with resistance. Then with
the second lead across 3-5 or 1-6 there is a slight movement again
and I cannot turn the motor by hand. Reversing the lead never seems
to make much difference in any test. Similar findings with 8-2
against 3-5 and 1-6. I'm not sure how to interpret these findings.
Since the axes were moving with the way the installer had it wired,
according to Jon, there is no need to continue to fool but just
leave it as he had it, since it moves and changing to other windings
will not help.
The Bridgeport manual shows the Sigma Windings. It has a wire
coming for instance from a small circle labelled 8 and continues
with a coil shape to a circle labelled 2. I assume that represents
one winding.
Mariss' drawings in the Gecko white paper show parallel and series
wirings of an 8 wire motor using all 8 terminals on the motor. He
does not show just wiring 2 of the 4 windings to the Gecko as we are
discussing doing here. He also mixes the terms series and parallel
with full and half winding. If done correctly, could I be more
successful with using all 8 terminals as he shows in the white paper
using a series or parallel configuration?
I hope Les Newell reads this and might be able to help me understand
why our machines are responding differently.
I hope we can get this all figured out for future generations of
Bridgeport fans...
thanks!
Keith Clark