94
Advanced Operation and Configuration
External Reference Junction
When using an external Reference Junction, MC5P measures or simulates the
thermovoltage using the “T/C Low V” terminals in the ET section. If the measuring/simu-
lating port is set to the External Reference Junction (ET: TCx(mea) or ET: TCx(sim)),
the following Reference Junction compensation methods are available:
0°C:
To be used when:
• The Reference Junction temperature is
fixed to 0°C (using, e.g. ice) and MC5P
is not used for measuring the Reference
Junction temperature.
• The Reference Junction temperature is
controlled with 0°C set point.
• A compensation box is used and the
Reference Junction temperature setting
is 0°C.
• There is no Reference Junction compen-
sation in the measuring/simulation cir-
cuit but 0°C is a good enough approxi-
mation.
Entered:
To be used when:
• The Reference Junction temperature is
fixed to a temperature that differs from
0°C.
• The Reference Junction temperature is
controlled and the controller’s set point
is not 0°C. Note: this method is of use
only if the accuracy of the controller is
better than MC5P’s own Reference
Junction Module.
• A compensation box is used and the
Reference Junction temperature setting
is other than 0°C.
• There is no Reference Junction compen-
sation in the measuring/simulation cir-
cuit, but you want to manually enter an-
other Reference Junction temperature
than 0°C.
Warning!
If you connect an RTD sensor to the ET
module’s R, RTD connectors, there is no
galvanic isolation between the thermo-
couple and the RTD sensor.
RTD sensor:
To be used when:
• The Reference Junction temperature is
measured using an RTD sensor con-
nected to MC5P’s RTD terminals.
Connection when measuring/simulating
thermovoltage using Reference Junc-
tion compensation method RTD sensor:
S/N
Max 60 VDC/30 VAC
OUTPUTSENSOR MEASURE & SIMULATE
T/C, Low V
4-w meas
R, RTD
V, I,
3 & 4-w meas
T
ref
Copper
T/C sensor
or a
T/C signal receiver
T/C materials
R, RTDT/C, Low V