Honeywell STT25D, Руководство оператора

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28 Smart Temperature Transmitter STT250 – Operator Manual
6.3 Installation/Commissioning
After wiring the meter as shown in Figure 14 and powering up the transmitter loop,
verify that the display operates as expected. The Smart Meter may require access to
its configuration push button which is accessible via a hole on the side of the
indication meter. This push button enables configuration of the preferred engineering
unit and meter zero/span calibration for a 4-20 mA signal.
When the loop power is applied, the Smart Meter runs a self test diagnostic for about
10 seconds to determine correct loop operation and, if a digital DE signal is present,
whether it is a 4 or 6 byte PV signal. Since most transmitters supplied with the Smart
Meter operate in 6 byte digital DE output mode, this approach is covered first. If
diagnostic displays are present on the meter (e.g. "
OUTPUT MODE ", " BAD XMTR
STATUS " or " FAULT-LAST KNOWN VALUE ") refer to Diagnostic and
Troubleshooting (Section 6.4).
6.3.1 Transmitter Operating in 6 Byte Output Mode
Press button on the side of the meter to scroll through the display codes to the
preferred engineering unit selection. The display codes are EU1, EU2, ..., EUF (and
CAL).
For the STT250: EU1 gives °C displayed on the LCD screen
EU2 gives °F displayed on the LCD screen
EU3 converts to °K (add on the stick-on label)
EU4 converts to °R (add on the stick-on label)
EU5 converts to mV (add on the stick-on label)
EU6 converts to Volts (add on the stick-on label)
EU7 converts to Ohms (add on the stick-on label)
EU8 to EUF gives % (of span) displayed on the LCD screen.
Ignore "CAL" at this stage or refer to Section 6.4.3.
Press and hold the button until the desired display code appears. Release the button
and the display reverts to the selected unit display. The Smart Meter is now
configured for use. Replace the meter cap.
6.3.2 Transmitter Operating in 4 Byte Digital Output or in 4-20 mA
Analog Mode
In these cases, the output signal does not include the transmitter database; only the %
of span output signal. Part of this database, (e.g. LRV/URV), is required to enable an
engineering unit display. Accordingly, press the "
ID " key on the SFC. If the transmitter
responds " DE XMTR XXXXXXXX " then also press the " SHIFT ", " ID " keys. This
enables the Smart Meter to recognize that the temperature units should be used and
the necessary part of the database to convert to the preferred engineering units. Now
configure the required engineering units as described in Section 6.3.1 above.
6.3.3 Transmitter Operating in 4-20 mA Analog Output Mode
The Smart Meter is factory calibrated to convert the received 4-20 mA signal to a 0 to
100% of span display. Regardless of the transmitter's actual PV output, a display of
0.0% output means that the meter requires recalibration. Refer to Section 6.4 for the
recalibration procedure.