Meriam MFT 4010 Modular Calibrator_HART Communicator - Manual (Page 102)

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Notes on RTD wiring
1. For maximum accuracy use 3-wire or 4-wire configurations with DIN Class A RTDs.
2. When using a 2-wire RTD, keep the lead length between the alligator clips of the general-
purpose connector and the RTD element as short as possible.
3. In 3-wire and 4-wire configurations, the wire size and length should be identical for all leads.
Option 2: RTD Measure Cable
IMPORTANT: Alligator clips on the connector/cable assembly must all be connected to something for
readings to take place!
RIO Measure Cable
P/N A900028-90500 general-purpose connector is used for connecting to RTD wires or terminals to obtain
temperature measurements directly from RTD devices. One pair of white and one pair of red Alligator clips
are suitable for connecting to 2-, 3-, or 4-wire RTDs.
2-wire
RTDs
Connect the two Red clips to one wire/terminal of the
RTD. Connect the two White clips to the other
wire/terminal.
3-wire
RTDs
3-wire RTDs have two wires/terminals that are the same
color. Connect the two Red clips to the wires/terminals of
the same color. Connect the two White clips to
the remaining wire/terminal.
4-wire
RTDs
4-wire RTDs have two wires/terminals of one color and two
of another color. Connect the Red clips to each of two
wires/terminals of the same color. Connect the White clips
to each of two wires/terminals that are the other color.
Note: Restrictions apply for use of Intrinsically Save RIO4000 modules / MFT units in Hazardous
Areas. RTDs and / or RIO4000 modules must only be removed or replaced in non-hazardous areas.
RTDs, P/N A900442-00026 connectors and P/N A900028-90500 User Cable must only be connected to
the RIO4000 in a non-hazardous area. See the Intrinsically Safe Control Document in the Appendix
for more details.
2.2 Measure Mode User Interface
2.2.1 Install the RIO4000 module in one of the MFT bays and turn on the MFT. If no RTD is connected to the
RIO module, the corresponding Sx line on the display will indicate “No Probe.” Be sure the RTD type is
correct - if not correct, go to the RTD Sensor Module Setup display to change the type.