Accu-Flo Meter Service TM Series, Руководство пользователя

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10
Environmental
Avoid plumbing meter where the 4-20 mA Out with Display is:
• Subject to constant exposure to water or other liquids (oc-
casional low-pressure splashing will not harm unit if cable
entry points are well-sealed).
• Subject to > 5g shock loading.
• Facing the sun directly for long periods of time.
• Close to high voltage/current runs, DC motors, internal
combustion engines or frequency inverters.
Cable Guidelines
4-20 mA Current Loop:
• The current loop itself is very resistant to electrical noise
pickup and shielded cable is seldom needed except in very
“noisy” (electrical) locations and/or when very long runs
(thousands of feet) are used.
Sensor Cabling:
• GX models come with 20 ft. of shielded cable.
• If you require a longer cable, a 100 ft. cable kit is available
from GPI, or use Belden 9363 cable. When wiring longer
lengths of cable, be sure to connect the shield to LOCAL-
COM only! (Multiple shield connections may cause ground-
loop problems).
• Some trial and error may be needed because of the wide
variety of user conditions. Try to keep cable lengths short!
Use the diagrams found in the Wiring Diagrams Section to cor-
rectly wire the system.
The display is externally powered by the loop.
Determine maximum power supply voltage after determin-
ing maximum allowable voltage of all electronic devices
in the system.
Connecting the Equipment:
• Remove the faceplate by removing the four (4) corner screws.
• Attach wiring from your equipment according to the follow-
ing terminal connections and wiring diagrams, depending on
your circumstances.
WIRING
CAUTION
Terminal Connections
Remote Transmitter INPUTS / OUTPUTS
ISO-IN COM: N/A
ISO-LF IN: N/A
ISO-HF IN: N/A
HL-LF IN: N/A
COIL-A IN: To flowmeter
COIL-B IN: To flowmeter
HL-HF IN: N/A
EDM PWR: Local Vcc. Regu-
lated 5-VDC internal power.
This terminal can supply up
to approximately 2.5 mA,
continuously, to external
circuitry. Typical load/line
regulation under ordinary
conditions is about ± 10%
LOCAL COM: Local Common
(2 places)
0-5 V OUT: 0 to 5 V Voltage
Output. Frequency to
Analog Output.
PULSE OUT: Pulse-Out
Frequency Output Signal. It is an “open-collector” output (also known as “n-p-n”
or “current-sinking”), referenced to transmitter Local-Common
LOOP (–): 4 to 20 mA Current Loop – current into transmitter
LOOP (+): 4 to 20 mA Current Loop – current out of transmitter
ISO-IN COM
ISO-LF IN
ISO-HF IN
HL-LF IN
COIL-A IN
COIL-B IN
HL-HF IN
EDM PWR
LOCAL COM
LOCAL COM
0-5 V OUT
PULSE OUT
LOOP (–)
LOOP (+)