Dynisco TX180, Инструкция по установке и эксплуатации

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TX180 Temperature Transmitter 23
pressing the
ENTER
key, or pressing the
NEXT
key changes to the next function.
4.10 T
RIM
20.0
M
A
Trimming of the 20.0mA current limit is done in exactly the same manner as was described for
trimming the 4.0mA point. The same precautions apply. After completing the trim 20.0mA pressing
the Next key brings up the display trim.
4.11 T
RIM
D
ISPLAY
The display trim allows the display to be trimmed by a desired offset amount. The transmitter display
will display its value based upon its internal standards. It is often desirable to alter this display to
make it agree with another external instrument at a critical measurement point. If this is desirable,
the display can be trimmed. The display trim operates as a zero shift. It shifts the display readings by
the same amount at every point.
You can enter a single point offset to the display. Be certain before making a display trim correction
that you have made good electrical connections to the transmitter and the sensor. In the 2 or 3 wire
RTD input, or thermocouple input modes, it is possible to produce an error of a few degrees with a
fraction of an ohm in any one of the connections. Please be careful when tightening down the input
connections. These can be easily broken if a lot of torque is applied. The idea is to make a good
electrical connection without breaking the connections. When you press the
ENTER
key the display
changes to
You can now enter an offset to the display. Suppose that the display reads 530
°
F, at a time when an
external device that you want to agree with reads 525
°
F. You would then want to enter a -5
°
F offset
in the display trim. This is done exactly the same way as setting the zero and full-scale values:
The numeric value seen on the upper portion of the screen is the existing Display Trim Value.
Normally this is set to zero. One can now change this Offset totally independent of the ZERO, or
LOWER RANGE VALUE, (LRV) or the FULL SCALE, or UPPER RANGE VALUE, (URV), without the
use of any calibrators or external sensor inputs. To change the display offset, press
ENTER
. The
display changes to
TRIM 20 MA?
0.0
°
F
TRIM
0.0
°
F
DISPLY?
0.0
°
F
PLUS?