IOtech MultiScan 1200, User Manual

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TempScan / MultiScan User's Manual Chapter 5: TempScan/1100 Scanning Cards 43
TempV/32B Description
The TempV/32B voltage scanning module contains 32 differential input channels and is capable of
measuring analog input signals on any of four programmable ranges: ±100 millivolt, ±1 volt, ±5 volt
and ±10 volt.
For differential input configuration, each input must have biasing currents. A certain amount of current
must be flowing into the differential inputs or else capacitance-induced noise will make the inputs
appear as noise.
The low side of each differential input channel is provided with a switchable 10-k
Ω
resistor to analog
common. This allows a current path when no current is flowing due to no common ground connections
or a high-impedance input source. With no common ground connection, closing the switch connects a
10-k
Ω
resistor between the (L) input and ground and provides a common mode impedance.
The relationships between the DIP microswitches and specific channels are described in the table.
TempV/32B Channel-to-Microswitch Relationships
Channel Microswitch Channel Microswitch Channel Microswitch Channel Microswitch
1 S6-8 9 S3-8 17 S5-8 25 S4-8
2 S6-7 10 S3-7 18 S5-7 26 S4-7
3 S6-6 11 S3-6 19 S5-6 27 S4-6
4 S6-5 12 S3-5 20 S5-5 28 S4-5
5 S6-4 13 S3-4 21 S5-4 29 S4-4
6 S6-3 14 S3-3 22 S5-3 30 S4-3
7 S6-2 15 S3-2 23 S5-2 31 S4-2
8 S6-1 16 S3-1 24 S5-1 32 S4-1