Measurement Computing Personal Daq/3000 Series - Manual (Page 29)

Connecting for Single-Ended or Differential
Voltage signals can be connected using the Single-Ended method. In the following figure voltage source
V1 is connected to Channel 0 and to analog common; and voltage source V2 is connected to Channel 8 and
analog common.
The figure also shows voltage V3 resulting from a thermocouple. In this case differential mode is being
used. The high line from the thermocouple is shown connected to Channel 1 HI and the low (negative)
side is connected to Channel 1 LO. Notice that Channel 1 LO uses the same screw terminal connection as
CH 9.
In Personal Daq/3000 Series and PDQ30 applications, thermocouples should only be
connected in differential mode. Connecting thermocouples in single-ended mode can cause
noise and false readings.
Personal Daq/3000 Series and PDQ30 devices do not have open thermocouple detection.
Thermocouple wires are to be connected in differential mode only.
Differential connection is made as follows:
(a)
the red thermocouple wire connects to the channel’s Low (L) connector.
(b)
the other color wire connects to the channel’s High (H) connector.
Single-Ended (V1 and V2) and Differential (V3) Connections to Analog Input Channels
Reference Note:
Appendix A, Signal Modes and System Noise, contains additional information.
Personal Daq/3000 Series User’s Manual 888594 Connections & Pinouts 2-5