Resistance Checks, Propulsion System Circuits; Dc Link Checks; Chopper Modules (Cm1, Cm2); Gate Driver Power Supply (Gdps) - Komatsu 930E-2 Shop Manual

Resistance Checks, Propulsion System Circuits:

4. Additional preparation
NOTE: Be certain preparations described in step 1.
have been completed.
a. Verify the PSC (17FL320) panel 104 pin con-
nectors are removed.
b. Verify the TCI panel connectors are removed.
c. Place the two Inverter Switches in the Informa-
tion Display Panel, on the side of the control
cabinet in the CUTOUT position (down).
d. Place the GF Cutout Switch, located in the
Information Display Panel on the side of the
control cabinet, in the CUTOUT position
(down).
e. Verify the Rest switch on the instrument panel
is in the REST state.
f. Disconnect the CCLR1 connector and the
CCLR2 connector located in the electrical cabi-
net, to the left of the AFSE.
g. Disconnect the RTN62 wire on TB4-D to re-
move the VAMS ground circuit.
h. Remove the wires on the GB1 ground block,
behind the AFSE. Make sure the lug on these
wires are not touching one another after the
wires are removed.

DC Link Checks:

NOTE: Use an analog meter (VOM) to measure resis-
tance in the following steps:
5. Place VOM positive lead on the DC plus link bus
(top bus bar) and the VOM negative lead on a
cabinet ground.
Resistance should be 2 megohms or
greater.
6. Place VOM positive lead on the DC negative bus
(bus underneath the positive link) and the VOM
negative lead on a cabinet ground.
Resistance should be 2 megohms or
greater.
7. Place VOM positive lead on the DC plus link and
the VOM negative lead on the DC negative link.
VOM must be on the Rx1 scale otherwise the link
capacitors will start charging and an accurate
reading will not be possible.
Resistance should be infinity (∞).
E3-6 AC Drive System Electrical Checkout Procedure
(Release 17 Software)
8. VOM positive lead on the DC negative bus and
the VOM negative lead on the DC positive bus.
On the Rx1 scale the resistance should be
approximately 5.5 ohms.

Chopper Modules (CM1, CM2):

9. With the VOM set on the Rx10,000 scale, meas-
ure the following at each Chopper Module in the
electrical cabinet (left side when facing cabinet).
GR(-) wire to ground - approximately 2 me-
gohms or greater.
GR(+) wire to ground - approximately 2 me-
gohms or greater.

Gate Driver Power Supply (GDPS):

Note: Verify 50 amp fuse (BATFU) is removed.
10. With the VOM set on the Rx10,000 scale, measure
the following at the Gate Drive Power Supply,
located in the electrical cabinet, below the Chop-
per Modules (left side when facing cabinet).
Terminal AI-1 (circuit #GDAI1) to ground - 2
megohms or greater.
Terminal AI-2 (circuit #GDAI2) to ground - 2
megohms or greater.
Terminal AI-3 (circuit #T305) to ground - 2
megohms or greater.
Terminal 1B+ (circuit #BATPO1) to ground -
approximately 1000 ohms or or greater.
Terminal 1B+ to terminal 1B- (circuit
#RTNO1) - approximately 1.0K ohms on the
Rx100 scale.
Terminal 1B- to ground - read 0 ohms.
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