Upright LX31, Service Manual

Page: 65 / 120

LX31/41 Electric Work Platform 4-15
T
RO U B L E S H O O T I N G
Section
4.9
Figure 4-3: Upright Tachometer Board
Battery Positive supply
(48 Volts)
A
No connection
B
No connection
C
Output over speed relay con-
nects to pin 7 of MOS90
D
Battery positive to over speed
relay (48 Volts)
E
D
Fuse
F1
Tach
Circuit
Over
speed
relay
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Battery Negative Supply
Tach speed signal to pin 12 of MOS90
Input from tach generator
Tach direction signal to pin 2 of MOS90
Input from tach generator
Tach generator
No connection
48 Volts = no over speed condition
0 Volts = over speed condition
2
Tach speed signal from tach board
7.5 Volts to 15 volts = 0-100% speed in FWD.
7.5 Volts to 0 volts = 0-100% speed in REV.
4
Tach direction signal
18 Volts = REV.
0 Volts = FWD.
3
5
Output of tach generator
0 to +50 Volts = 0-100% speed in FWD.
0 to -50 Volts = 0-100% speed in REV.