Dynisco TX180, Инструкция по установке и эксплуатации

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transmitter. Connect the - side of the power supply to the - terminal of the transmitter.
Connect a Type J thermocouple to the transmitter input.
Thermocouple high (+) (input terminal 2)
Thermocouple low (-) (input terminal 1)
Jumper terminals 3 & 4 together
Unlike conventional electrical wiring, (on a J thermocouple the red lead is negative) . This should be
checked and verified with the particular sensor to be used.
To connect other sensors to the input refer to Section 2.3.2 for the proper sensor connections.
The output can be monitored by connecting a milliammeter in series with either of the two output
terminals, or by connecting a high impedance voltmeter across the optional 250 ohm resistor. Now
turn on the power supply. In about 5 seconds the TX180 loop current will settle to its normal value
in the range of 4 to 20mA, unless the input terminals are open, in which case the output current will
be 23.00mA. Note that for a Type J thermocouple, if 4mA = 40
°
F and 20mA = 200ºF, each
additional 10
°
F increases the current by 1.0mA.
3.1.3 O
PERATION
W
ITH A
D
ISPLAY
If the transmitter was ordered with either display option, it will have a small local LCD display
module (with two integral buttons) plugged in to the top of the unit. Either display option can be
ordered already installed on the TX180 transmitter. Alternately, either display can be ordered and
field installed at any time.
Having the display option as part of the transmitter does not affect its operation in the analog mode
and the description of the previous section applies. However, the display option does provide some
very useful local indication of the measured temperature and other diagnostic functions. Figure 6
below indicates the arrangement of the display screen.
Fig. 6 Local Displays, LI-1 and LI-2