Secondary Power Unit - Selco Genesis 200 AC-DC Repair Manual

9.4) SECONDARY POWER UNIT

9.4.1) SECONDARY POWER UNIT G 200 AC- DC (fig. 24)
This unit handles secondary power rectifying and AC switching.
WARNING!: Before commencing the measurements described, make sure the HF board is disconnected from the bus
board!
WARNING!: should module IGBT break and be replaced, board 15.14.253 (see sect. 9.7 below) must be tested befo-
re reconnecting board 15.14.289 (a faulty IGBT module can break the 15.14.253 board and vice versa)!
26 26
Unless otherwise specified, all measurements sholud be taken with the boards in their slots and connected accordingly
Power source / Mode Test point
OFF R GA
OFF R GB
OFF V A
ON / MMA V GA
ON / MMA V GB
ON / MMA V 3
ON / MMA V 1
ON / MMA V out*
· note: Vout = power source's open circuit voltage OCV
WARNING!
1) Components sensitive to electrostatic discharges.
2) Torque wrench settings:
FASTENING ON HEAT SINK
BOARD FASTENING
3) Use layer of thermal grease
Value
SA 10 k
SB 10 k
K +0.3 Vdc
SA -13 Vdc
SB +13 Vdc
1 +0.5 Vdc
2 +105 Vdc
+52 Vdc
= MAX 1.5 Nx m / 13 lb x in
= MAX 1.5 Nx m / 13 lb x in
Description of boards