Watlow Electric Revision 5 - Manual (Page 30)

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5.6.4 DC CURRENT INPUTS
Current inputs from transmitters are accommodated by placing resistors in
the input section to convert the current input into a voltage. Different
current input ranges are accommodated by selecting the proper resistor
values. In general RC is selected to maintain a low source resistance. RA
and RC produce the input full scale of 60mv. The positive input should be
connected to the AUX terminal, and the negative input to the LOW
terminal. The following input values are suggested:
4 to 20 ma 0 to 10 ma
RA = 93.1 ohms RA = 26.7 ohms
RB = 20.0 ohms RB = 20.0 ohms
RC = 20.0 ohms RC = 20.0 ohms
Load resistance=17 ohms Load Resistance=14 ohms
A single 0.1% resistor may be used in place of the above resistors although
a small error may occur. This error can be corrected in using the scaling in
ANASOFT.
4 to 20 ma 0 to 10 ma
RB = 3.000 ohms RB = 6.000 ohms
Please note section 5.6.2 regarding the shield connection.
Please note section 5.8 regarding scaling and calibration.
5.6.5 THERMOCOUPLE INPUTS
All thermocouple types may be directly connected to the ANAFAZE
SYSTEM 32. Types J,K,T,R,S,C, and B linearization and cold junction
compensation are provided standard in the ANAFAZE SYSTEM 32. For
other thermocouple types, optional input ranges are required.
Thermocouples should be connected with the positive lead to the HIGH
terminal and the negative lead to the LOW terminal. Note section 4.5 on
shielding.
5.6.6 RTD INPUTS
RTD's can be connected in different configurations including bridge
circuits, three wire and four wire -- please request a copy of the ANAFAZE
RTD application bulletin.
The standard industrial RTD is a 100 ohm Platinum three wire assmbly.
THE ANAFAZE SYSTEM 32 WILL BE CONFIGURED FOR THE
STANDARD THREE WIRE RTD INPUT UNLESS OTHERWISE
SPECIFIED.
ANAFAZE recommends using only the 3-wire or 4-wire RTD configuration
for high accuracy.
Due to multiple ranges, different RTD range resistors, and special
linearization of the RTD range for high accuracy, the RTD INPUT should
be factory installed. If less accuracy is acceptable, please request the
ANAFAZE RTD application bulletin to field install the RTD input.