18
Note:
Wound up measuring lines may cause erroneous
measurements due to inductivities.
4.4 Measuring
After measurement setup (see 4.2) and zero balan-
cing (see 4.3), the measuring instrument is ready for
operation.
You can perform standard or automatic measure-
ments with or without pole changing. Direction of
current flow is indicated in the display as “+“ or “-“.
The displayed sign refers to the test probe.
If necessary, clean the measurement point from
corrosion or paint
Attention!
Measuring point must be free of voltage (see 4.7).
Switch on the device with button
(+ 1 and
the green LED signalizes that the device is ready
for measurement).
Place the test electrode onto the measuring point
vertically if possible and assure safe contact.
If the red LED flashes and you hear an acoustic
warning signal, an external voltage is present! The
test must be interrupted (see 4.7).
Short warning signals can be caused by inductive
voltages or statical charging which has no influence
on the measurement.
4.5 Standard measurements
Hold button
pressed until a constant
measurement value is displayed.
With measurement values <10
Ω
the
EP 4 automatically switches to Lo-
Ω
mode
and continues measuring with a measurement
current of 200 mA.
The display shows the symbol „Lo-
Ω
“ and the
right LED signalizes 200 mA measurement
current. If the measurement value is out of
measurement range (>1999 k
Ω
) the symbol “OL“
(Overflow) appears on the display.
Change of polarity:
After measurement with positive polarity (s.o.):
press button
+/-
(“-1“ and green LED display readi-
ness for measurement with different polarity).
Perform negative measurements the same way.
Large deviations between values are an indica-
tion for application of galvanic voltage. Repeat
both measurements. If the results are similar to
those that were taken before, an average value
between the “+“ and “-“ may be assumed.
