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is low (eg less than 10.8VDC), or even stop the phenomenon of self-test you should first
ensure power supply (or cable) Is there a problem, you can pass a single 24VDC power supply
confirmation.
Meter anti-jamming measures requirements: due to the higher degree of intelligence (eg
Hart communication), the instrument corresponding anti-jamming measures require a
corresponding increase.
Meter site installation environment requirements: Avoid the vicinity of large motor
and frequency conversion equipment exists.
Power Requirements: Requires voltage stable, clean, avoid large start-stop device, stop
transmission and other state interference spikes occur; in the event of power failure, after
power transmission equipment, and then Turn on the meter. Cable Requirements: determine the
field instrument cable is a shielded cable and the shield has a good instrument ground.
(Be careful not to mix with electrically connected, there should be a separate grounding
instrument).
Cabling requirements: instrument cable and power cable can not be in one piece (the
same as in stir-phase bridge, etc.), to separate the individual.
Load requirements: General requirements for the load carried by the output current of 250
ohms to 750 ohms. 750 ohm load is greater than the output current can be smaller or hopping.
But less than 250 ohm load is not recommended, otherwise interference ability. If the
recommendation is to go directly to the scene received 4 ~ 20mA current second table or
DCS, the load is small, you can string a 250 ohm resistor in the loop, there can be
interference effect.
Current output problem detection process: positioning indicator whether the removal of
the replacement Check fastening screws pointer check the float shaft Indicates
whether the starting point pointer RP Push the float detected current Current
adjustment
With switching indication and alarm detection plate:
Indicating detection: If the operation is not flexible indicating a problem and needs to
detect pointer fan-shaped plate and start switch board mating problems. Alarm can first
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