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3.2.8 Current measurement
Do not attempt to measure the current in a circuit if the voltage between the open-circuit voltage
and the ground is over 250 V. If the fuse is blown at the moment of measurement, you are likely
to damage the multimeter and get yourself hurt.
To avoid any damage to the meter or equipment to be measured, do not measure the current unless you have
examined the meter’s protective tube. For the measurement you should use the correct input sockets, function
positions and measuring ranges. When a test lead is inserted into the current input socket, do not put the other
end of the test lead in parallel connection with any circuit.
The meter provides DC current measuring ranges as follows: 60 μA, 60 mA, 600 MA and 20 A.
AC current measuring ranges: 60 mA, 600 mA and 20 A.
Current measurement:
1. Turn the function switch to the appropriate position.
2. Connect the test lead in black to the COM input socket. Connect the test lead in red to an mA input socket when
the measured current is less than 600 mA. Connect the test lead in red to a 20 A input socket when the measured
current is 600 mA up to 20 A.
3. Disconnect the circuit to be measured. Connect the test lead in black to one end of the disconnected circuit and
connect the red test lead to the other end of the disconnected circuit.
4. Connect the power to the circuit and capture the displayed reading. If the display unit only shows “OL“, it means
that the value is higher than the selected measuring range. In this case, turn the rotary switch to a higher measuring
range.
3.2.9 Anode measurement
Only anodes and impressed current anodes that are installed insulated can be tested.
The digital multimeter can be used to check the state of sacrificial anodes in DHW storage tanks without
having to remove them. This test is carried out via DC measurement between anode and storage tank.
The anode must not have a direct electroconductive connection to the storage tank wall. The measurement
is conducted via series switching of the measuring instrument between anode thread and storage tank wall.
The instrument provides the following measuring ranges for direct current: 60 μA, 60 mA, 600 mA and 20 A.
Anode measurement:
1. Turn the function switch to 60 mA.
2. Connect the lead in black to the COM input socket. Connect the lead in red to the 60mA input socket.
3. Connect the lead in red to the thread of the anode and connect the lead in black to the storage tank. If the display
only shows “OL”, this will mean that the value is higher than the selected measuring range. In this case, please set
the rotary selector switch to a higher measuring range.
4. Perform the current measurement without interruption until the value is normal. In most cases, this will happen
after approx. 30 seconds. Now take the indicated measurement result.
Digital multimeter
GB