9-  50 Service Guide  LWE180, LWE200, LPE200, LPE240 © BT Europe AB
Electrical System – 5000 LWE 180/200 LPE 200
Part number
T-code Valid from serial number Date Order number
660, 661, 662, 497  723984- 2005-05-11 225553-040
9.7  Part number
• Press and hold S18 while turning S17 to “ON” position.
• Press S18 until Pn = part number is displayed.
• You have now selected Pn = part number and the symbol ”D” is lit as 
an indication of what is now shown in the display. Initially, Pn = 
number is displayed for the component’s entire unit.
• By scrolling with L1, you can get the following information:
• SPn = Part number for software.
• HPn = Part number for hardware.
• HSn = Serial number for hardware.
9.8  Transistor panel
9.8.1 General
Curtis 1243 is a regulator that controls shunt motors. What primarily 
controls the speed is the variation in the voltage in the rotor.  The volt
-
age is varied by means of pulse width modulation (PWM). This also 
includes variation in "on" time for the MOS transistors that regulate the 
rotor current.
The rotation direction is changed by changing the polarity in the field 
winding (S1-S2). The regulator is equipped with a transistor-fitted four-
quadrant bridge for the field winding and a single-quadrant bridge for 
the rotor winding.
A
B
C
DE
MODEL
STATUS
SERIAL
VOLTAGE
CURRENT
M
A1 A