75
Standard resistor
(1 or 10
Ω
)
Digital voltmeter
To CK +
To CK –
Maintenance
Check of arrester :
• Measure output current from the transmitter check terminals and output current to
fl
ow
into transmitter (see
fi
gure 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 CK+ and CK-
Output measurement outside transmitter
* Disconnect the wire from the – (minus) terminal and connect the measurement device a
shown below.
Standard resistance
To (+) side wiring
To (+) terminal
To (–) terminal
To (–) side
wiring
DC power
supply
Digital voltmeter
