VTI Instruments Metek EX1202 User Manual page 96

VTI Instruments Corp.
4-Wire Measurement Connections
The 4-wire RTD measurement method is the most accurate method of the two methods, as the set
up automatically removes connection lead and switch resistance. This method does, however, does
increase setup cost, as additional cabling is required.
If the RTD is connected to a multiplexer card, the wiring is similar to that used for 4-wire
resistance measurements (Kelvin method). To properly operate an EX1200 multiplexer cards in
4-wire mode, refer to the EX1200 Switch Card User's Manual for more information.
96
DMM Backplane
EX1200 Mainframe
F 4-16: RTD 2-W
IGURE IRE
Sense HI
Input HI
Input LO
Sense LO
DMM Front Panel
F 4-18: RTD 4-W
IGURE
CH 1
CH 2
CH n
EX1200
Multiplexer Cards
C EX1200 DMM B
ONNECTION VIA THE
C DMM F
IRE ONNECTION TO
RTDs
US
RTD
P
RONT ANEL
Basic EX1200 DMM Operation