©Isothermal Technology
Page 30 of 61
914 millisKanner manual Iss. 1.00
500\
Ω
resistance uncertainty. With a 1mA sense current, this corresponds to a voltage
uncertainty of 0.5\V.
The millisKanner and milliK are optimised for electromagnetic compatibility (minimising
emissions and maximising immunity). However, since the milliK is capable to measuring
to such low signal levels it is worthwhile adopting good electrical measurement practices.
Here are a few guidelines:
The most sensitive points are the inputs to the millisKanner or milliK (measuring to
better than 0.5\V). Whilst the millisKanner and milliK will work satisfactorily with
just a four-wire connection to the PRT or thermistor, it is better to use a screened
cable and to connect the screen to the measurement ground terminal above the
input terminals:
R
B
R
B
G
RED
BLACK
RED
BLACK
GREEN
I
V
Screened Cable
The screen should also be connected to the outer sheath of the PRT (if it is metal
clad). The use of screened cables is more important when the milliK is used with
thermistors, which have a higher resistance than PRTs or thermocouples.
Keep the cables to the millisKanner and milliK input terminals away from other
cables that might be sources of electrical noise (for example electrical supplies to
furnaces).
The insulation in high temperature furnaces (any that ‘glow’) begins to conduct at
higher temperatures. This can cause high common-mode voltages on any
