VTI Instruments Ametek EX1200A Series, User Manual, Page: 101 / 165

VTI Instruments Corp.
100 EX1200A Triggering
DMM Backplane
B
P
L
_
H
I
B
P
L
_
L
O
B
P
L
_
S
H
I
B
P
L
_
S
L
O
CH 1
CH 2
CH n
RTDs
EX1200
Multiplexer Cards
EX1200 Mainframe
F
IGURE
4-16: RTD 2-W
IRE
C
ONNECTION VIA THE
EX1200A DMM B
US
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.
DMM Front Panel
Sense HI
Input HI
Input LO
Sense LO
RTD
F
IGURE
4-18: RTD 4-W
IRE
C
ONNECTION TO
DMM F
RONT
P
ANEL
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 EX1200A multiplexer cards in
4-wire mode, refer to the
EX1200A Switch Card Use
r’s Manual
for more information.