Operation Of The Module; Module Power Supply - Hameg HM8001-2 Benutzerhandbuch

60­minutes­before­starting­the­test.­The­specified­
alignment procedure should be strictly observed.
When removing the case detach mains/line cord
and any other connected cables from case of the
mainframe HM8001-2. Remove the screws on
rear­panel­and,­holding­case­firmly­in­place,­pull­
chassis forward out of case. When later replacing
the case, care should be taken to ensure that
it­properly­fits­under­the­edges­of­the­front­and­
rear frames. After removal of the two screws at
the rear of the module, both chassis covers can
be lifted. When reclosing the module, care should
be taken that the guides engage correctly with the
front chassis.
Cleaning the HM8001-2
The exterior of the mainframe should be regularly
cleaned with a small brush. Stubborn stains on
case, handle, plastic and aluminium parts should
be wiped with a damp cloth (water +1% mild de-
tergent). Remove grease with methylated spirit
or a suitable spirit-based cleaning agent. Utmost
care should be taken to ensure that no cleaning
fluid­drops­inside­the­instrument.

Operation of the module

Provided that all hints given in the operating
instructions of the HM8001-2 Mainframe were
followed especially for the selection of the cor-
rect mains voltage start of operation consists
practically of inserting the module into the right or
left opening of the mainframe. The following pre-
cautions should be observed: Before exchanging
the module, the mainframe must be switched off.
A small circle (o) is now revealed on the red power
button in the front centre of the mainframe. If the
BNC sockets at the rear panel of the HM8001-2
unit were in use before, the BNC cables should
be disconnected from the basic unit for safety
reasons. Slide in the new module until the end
position is reached.
Before being locked in place, the cabinet of the
instrument is not connected to the protective earth
terminal (banana plug above the mainframe mul-
tipoint connector). In this case, no test signal must
be applied to the input terminals of the module.
Generally, the HM8001-2 set must be turned on
and in full operating condition, before applying any
test signal. If a failure of the measuring equipment
is detected, no further measurements should
I m p o r t a n t h i n t s
be performed. Before switching off the unit or
exchanging a module, the instrument must be
disconnected from the test circuit.

Module Power Supply

All supply voltages required for module operation
are generated by the built-in power supply unit
of the HM8001-2. As already mentioned, both
module compartments are electrically separate
from each other. The multipoint connectors in
the module compartments are numbered from
1 to 22. Further markings indicate the type of
voltage and potential across the terminals. In
some cases, several different types of voltages
or even different values can be drawn from one
voltage source, as can be seen from the diagram
(see next page) and from the circuit diagram. The
AC voltages of the secondary windings are applied
to the terminals marked V
voltage regulation therefore can be carried out in
the modules if desired.
In case the HM8001-2 is equipped with the option
HO801, no. 1 and 2 contacts are directly connected
to the rear panel BNC terminals, through which
signals are fed or supplied in some modules.
They can also be connected to control points in
the modules.
Caution! A potential higher than 42 V
must not be applied under any circum-
stances.
Subject to change without notice
.­Rectification­and/or­
AC
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