Keysight DAQ970A User Guide

DAQM902A 16-Channel Reed Multiplexer
DAQM908A 40-Channel Single-Ended Multiplexer
An important feature of a multiplexer used as a DMM input channel is that only one channel is connected
at a time. For example, using a multiplexer module and the internal DMM, you could configure a voltage
measurement on channel 1 and a temperature measurement on channel 2. The instrument first closes the
channel 1 relay, makes the voltage measurement, and then opens the relay before moving on to channel
2 (called break-before-make switching).
Other low-level switching modules available with the DAQ970A include the following:
DAQM903A 20-Channel Actuator
DAQM904A 4×8 Two-Wire Matrix
One-Wire (Single-Ended) Multiplexers
On the DAQM908A multiplexer, all of the 40 channels switch the HI input only, with a common LO for the
module. The module also provides a thermocouple reference junction for making thermocouple meas-
urements.
Only one channel can be closed at a time; closing one channel will open the previously closed chan-
nel.
Two-Wire Multiplexers
The DAQM900A, DAQM901A, and DAQM902A multiplexers switch both HI and LO inputs, thus providing
fully isolated inputs to the internal DMM or an external instrument. These modules also provide a ther-
mocouple reference junction for making thermocouple measurements.
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212 Keysight DAQ970A User's Guide

Keysight DAQ970A Specifications

General

Scan Rate	Up to 450 channels/sec
Connectivity	USB, LAN, GPIB (optional)
Display	4.3-inch color LCD
Operating Temperature	0 °C to 50 °C
Number of slots	3 slots
Measurement Types	DCV, ACV, DCI, ACI, 2-wire resistance, 4-wire resistance, frequency, temperature, capacitance
Voltmeter	6.5 digit
Resolution	22 bits
Memory	Non-volatile memory