Magontec CorroScout 500 Notice D'utilisation page 31

Advice: In carrying out measurements on electrical tubular heaters,
the execution of the test must be carried out with the voltage
supply to the electric heater interrupted for reasons of electrical safety!
4.5 Testing the drive potential
If a CORREX
actual drive potential of the anode against the tank is always possible,
because of the electrically insulated installation of the titanium anode.
For Mg sacrificial anodes, testing is only possible in the case of an
insulated anode installation (see above). The drive potential measu-
rement is of special importance when testing CORREX
current anodes. The drive potential of Mg sacrificial anodes requires
the selection of the 2 V DC range; the corresponding measurement
for CORREX
DC range.
The measurement at the CORREX
system is described below.
Measurement is carried out as follows:
1. Turn the rotary switch of the CorroScout
(Drive potential) in the 20 V measuring range.
2. Connect positive pole (red) of the CorroScout
anode and the negative pole (black) to the tank.
3. Read the drive potential. With correct polarity the voltage shown
on the LC display must have a positive (!) value.
Assuming correct polarity, the drive potential between titanium
anode and tank mass with enamelled storage tanks should be not
less than U = + 2.3 V. In the case of water with lower conductivity,
the drive potential can also show values of a few (single digit) volts DC.
To test the functionality of Mg sacrificial anodes, usually the already-
mentioned protective current measurement is used. The measure-
ment of the drive potential is comparatively less meaningful. The
drive potential for the system of Mg sacrificial anode and enamelled
storage tank is usually in the region of several hundred millivolts DC.
® impressed current anode is installed, testing of the
® impressed current anodes are carried out in the 20 V
CorroScout ® 500 Operating Instructions
® impressed current anode
® 500 to "Treibspannung"
®
® impressed
500 to the titanium
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