Siemens S5-135U/155U System Manual page 461

If you have preset measurement with respect to ground on switch S9, four
channel groups of four channels each are available. You can configure each
channel group separately for current or voltage measurement.
This is set with switches S5, S6, S7 and S8. Switches S5 and S7 allow three
settings (left, midpoint and right); switches S6 and S8 allow two settings (left
and right). The switch settings relate to the locations on the module shown in
Figure 9-26:
Setting the current/voltage measurement for channel group I
Setting the current/voltage measurement for channel group II
Setting the current/voltage measurement for channel group III
Setting the current/voltage measurement for channel group IV
System Manual
C79000-G8576-C199-06
Channel Group I
(Channels 0 to 3)
Current
Voltage
Channel Group II
(Channels 4 to 7)
Current
Voltage
Channel Group III
(Channels 8 to 11)
Current
Voltage
Channel Group IV
(Channels 12 to 15)
Current
Voltage
Analog Input/Output Modules
Switch S5
Switch S7
Switch S6
Switch S8
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