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47DR OPERATING MANUAL EM-9509-B Rev.7
1.7.4 WIRING INPUT SIGNAL
CConnect a RTD.
IMPORTANT
• Use wires of the same type, width and length.
• The leadwire resistance including internal resistance such like a lightning surge protector and a barrier must be maxi-
mum 20 Ω per wire.
• The sensing current is 1 mA for Pt 100 (JIS ‘89), Pt 100 (JIS ’97, IEC) and JPt 100 (JIS ’89), 2 mA for Pt 50 Ω (JIS ’81),
and 0.1 mA for Pt 1000. Use an RTD with the specified current or more.
• Take measures to reduce noise as much as possible, e.g. by using shielded twisted pair wires for the input signal.
Ground the input shield to the most stable earth to prevent noise troubles.
• Do not connect anything to unused terminals.
RTD input
Ground
(resistance
100 ohms or less)
RTD
A
B
B