BENNING MA 4 measuring adapter
5
5. Connecting the measuring adapter
The measuring adapter is equipped with a PTC ther-
mistor as short-circuit protection for cable testing, but
not for appliance testing.
Use the measuring adapter only for the intended tests
described in this manual.
The manufacturer
s’ specifications or normative re-
strictions with regard to all tests involved must be ad-
hered to.
To do this, thoroughly read the notes stated in the
corresponding standards, in the manufacturers’ speci-
fications of the test sample and in the operating man-
ual of the appliance tester.
Before you can start testing, you have to connect the measuring
adapter to your appliance tester.
To do this, proceed as follows:
Make sure that the appliance tester you are using is ready
for operation.
Connect the shock-proof plug of the measuring adapter to
the test socket of your appliance tester.
Connecting the measuring adapter to the appliance tester
This is a connection method for appliance testing and cable
testing.
For appliance testing, the MA 4 must be connected to the
mains. Connect the ST 755 / 760 to the socket of the MA 4.
Connection diagram
6. Testing with the measuring adapter
Testing the adapter for compatibility with third-
party manufacturers / self-testing the device
In the switch position for appliance t1 mA and
in the switch position for appliance t3 mA, an
internal fault current is generated in the MA 4. The
fault current becomes detectable for the measuring
instruments when 230 V are applied to their test
socket. For appliance testing, the MA 4 must be con-
nected to the mains via the CEE 32 A cable. If such
a functional test is carried out, no fault current is gen-
erated in the switch position for appliance testing
without any test samples being connected. By select-
ing the position for appliance t1 mA, a fault
current of approx. 1 mA is generated. The fault cur-
rent depends on the mains voltage. Now, it should be
possible to measure this fault current by means of the
tester. The fault current is applied on the N conductor
and on the PE conductor of the measuring instru-
ment.
The current in the N conductor can be determined by
any measuring instrument using the differential cur-
rent measuring method. In order to detect the applied
current in the PE, a measuring resistance of 1
kΩ is
required. Otherwise, a deviating applied fault current
will occur. In case of the ST 755 / 760, this load is au-
tomatically selected as soon as three-phase meas-
urement has been activated.
For this test, no test sample may be connected!
Before carrying out the functional test and all tests
for which the test sample must be supplied with
mains voltage and put into operation, make sure
that there are no short-circuits in the test sample
within phases L1, L2, L3 and the neutral conduc-
tor N! Non-observance might involve damaging or
destruction of the measuring adapter and possibly of
the test sample as well!
Within the framework of the functional test, it is not
possible to determine the values of the power and
current consumption of the test sample by means of
the measuring adapter. The displayed values refer
to the power consumption of the measuring adapter
itself.
