Rosemount 2240S, Справочное руководство

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Reference Manual
300550EN, Rev AA
December 2010
6-9
Rosemount 2240S
Section 6. Service and Troubleshooting
6.2.7 Test and
Simulation
Test Terminal for Temperature Elements
The Rosemount 2240S has a built-in simulator for temperature elements
which allows you to verify the measuring electronics.
The built-in test facility comprises one 100
±
0.1 Ohm resistor and four 10
±
0.1
Ohm resistors to simulate a temperature element (RTD) with a long cable
connection.
To check a measuring channel:
1. Connect the test terminals to the corresponding input terminals as shown
in table Table 6-2:
Table 6-2. Test terminal
connections
2. Check the connected input channel. It should read 0
±
0.3°C (4-wire
independent spot), 0
±
0.6°C (3-wire independent spot) or 0
±
6°C (1-wire
common return).
Figure 6-5. Test terminal for
temperature elements
4-wire 3-wire 3-wire common return
(1)
(1) To check a channel for 3-wire common return operation, the element on
channel 1 must be disconnected and replaced by the test terminal c and d
connections
a - a
b - b
c - c
d - d
a - No connection
b - b
c - c
d - d
a - No connection
b - b
c - 1c
d - 1d
a
b
c
d