
GEOHM 5
Instrument description
15
Step 2
Set function switch to
”
“ position, the following menu will be displayed.
Figure 9 Earth Resistance initial menu
Step 3
Press START key and view the test result. (If you want to perform
more than one measurement press the
START
key and keep it
pressed until the result has stabilized, than release the key. The last
result will stay displayed.)
Press the DISP key to check the resistances of both the potential
(
Rp)
, and the current (
Rc)
test probes. After a short period
the main
result will automatically be displayed again.
Store the displayed result for documentation purposes, see instructions how to use
memory in chapter 3.1.1. Storing of test results.
Notes!
When an external voltage higher than 20 Vac/dc. is present between the H and E
or ES and S test terminals, the Earth Resistance measurement will not be carried
out after pressing
START
key, but the message
> 20 V
will be displayed, marked
with
!
symbol!
If a noise voltage higher than approx. 5 V is present between the H and E or ES and
S test terminals, a cursor mark pointing to the
“
” (noise) symbol will be
displayed, indicating that the test result may not be correct!
If the resistance of the current or the potential rod is too high (>(4 k
+ 100 RE) or
>50 k
, whichever is lower), the test result will be marked with
symbol and the
cursor will appear on
Rc
and / or
Rp
.
If the test result is out of the measurement range (open test leads),
>19,99 k
message will be displayed!
If the current measured with the sensitive test clamp is lower than 0,5mA, the
cursor will appear on
Low I
C
(low current), indicating that the test result may not be
correct!
This can happen if measuring a large lightning system or in cases of high current
rod resistance.