Connecting Current Loop Inputs To Voltage Channels - Data Translation DT9871 User Manual

Connecting Current Loop Inputs to Voltage Channels

Voltage channels on the DT9873 and DT9874 instruments have an input range of ±10 V or
±60 V. You select the input range for each channel using software.
With the 24-bit A/D converter, high current, high side current shunts can be used for
resolutions of less than 0.01 A on a 100 A range.
Typical Shunts:
• Vishay WSMS5515
.2 m - 2W - 100A - 20mV
• Vishay CSM2512S
10 m - 1W - 10A - 100mV
• Deltec MUB-500-50
.1 m - 25W - 500A - 50mV
Notes: On the DT9874 instrument, channels 32 to 47 correspond to the voltage input
channels.
Figure 23 shows an example of wiring signals to measure ±20 mA using the ±10 V input
range.
Figure 23: Connecting a Current Loop Input to a Voltage Channel to Measure ±20 mA
Voltage Channel
– Sense +Sense
4 3 2

250
±20 mA shunt resistor
Load
In this example, the input range is ±10 V.
1
Shield
+
28 V (can be up to ±60 V)
–
Wiring Signals
59