Fujimoto Fuji Differential Pressure Transmitter FKK 4 - Manual (Page 68)

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♦ Check of arrester
• Measure output current from the transmitter check terminals and output current to flow into
transmitter (see figures below).
When current is measured with an ammeter connected to CK+ and CK- terminals, the
internal resistance of the ammeter should be 12
Ω or less.
• If the measured two output current are the same, the arrester is normal.
• In case the measured values have a difference of 0.1% (0.016mA) or more, the arrester is
not functioning.
• In the above case, the arrester unit (terminal unit) should be replaced with a new one.
♦ Limitation of insulation resistance and dielectric strength test
An insulation resistance and dielectric strength test should be avoided as a rule, since it
may damage the arrester.
Output measurement at check terminals
To CK +
Standard resistor
(1 or 10Ω)
To CK –
Digital voltmeter
Standard resistance
Digital voltmeter
To (–) terminal
To (+) terminal
DC power
supply To (+) side wiring
To (–) side
wiring
Maintenance
Output measurement outside transmitter
* Disconnect the wire from the - (minus)
terminal and connect the measurement device a
shown below.