50/100 Ohm Check - Classe Audio Delta Series Service Manual

Check that the main fuse and the internal fuses are correct for 120Vac operation (see Appendix A). Also verify
that the internal fuse-holders are tight.
If you are using 120Vac power, verify that the first and last (but no other) jumpers are present on Voltage
Selector (VS connector) on the AUX Power Supply board. Verify that the single jumper on connector CON1 is
in the 120Vac position.
Verify the wiring on the push-on terminal wiring on the AUX PS. The wire colors and their corresponding
connections (for 120Vac, from left to right) are:
Connector Color
LIN2
X4
X3
NEU
NEU1
N
X1
X2
R0
X9
X8
X7
X6
X5
R1
LIN1
LIN
NOTE: Cable colors DO NOT uniquely identify the cables. Please use the cable colors in conjunction with the
"To or From" wiring information.
NOTE2: To reconfigure for 230Vac operation, move the blue connector from X1 (not just ANY blue
connector) to X6 and the orange connector from X4 to X5. On the AUX PS board switch the single jumper on
CON1 to the 230Vac position. Also remove the two jumpers from connector VS and place a single jumper in
the middle position on the same connector. This unit will protect itself from a wrong AC voltage but for this
protection to work you must ALWAYS match the settings on connector VS with the setting on connector
CON1.
Before you power-up the unit check that the DC cables (main rails, MOSFET rails, and grounds) on the
heatsink boards are correctly plugged in. Also, measure the 10-ohm soft-start resistor (on the chassis) to
confirm its value.

50/100 ohm check

With the unit unplugged, measure the resistance between analog ground (output ground) and chassis ground
(AC plug GND). It should measure 50 ohms (it's a 49.9 ohm resistor). Make sure it is NOT a short. Also,
make sure that your RS-232 cable is not connected to the unit; in this case, it will short the ground and gives
5.5 ohms For the CAP-2100, check the impedance between the ground from the output and the metal casing
of the TFT. You should measure open or not defined resistance. If you have a short, change the TFT right
away.
CA(P)2100 AMP Service Manual v1.4 inc voltage change info .doc
To or From
White From L2 on AC-sensor board
Orange Main transformer primary
White Main transformer primary
Blue Neutral Filter board
Blue Neutral Filter board
Blue AC-sensor board
Blue Main transformer primary
Black Main transformer primary
Black To 10ohm soft-start resistor
Brown Main transformer primary
Yellow Main transformer primary
Grey Main transformer primary
N/C
N/C
Black To 10ohm soft-start resistor
Brown From N6 on AC-sensor board Line for main transformer
Brown From N6 on AC-sensor board Line for main transformer
Description
Line for AUX PS
Primary A: Top
Primary B: Top
Filtered main power neutral
Filtered main power neutral
Neutral for AUX PS
Primary A: 115V
Primary B: 115V
N/C
N/C
N/C
Tied to X5
Tied to X6
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