Applications - Megger AVOMETER 8 Mk7 Guia Del Usuario

3 has 60 divisions and is used for a.c. and d.c.
current and voltage measurements.
CUT-OUT
The sensitive cut-out, with very positive latching
action is triggered by the meter movement when
overloaded i.e. when the pointer deflects rapidly
to beyond the full scale position. The cut-out is
reset by a push-button on the front of the meter.
The 'off' position on the left-hand switch selects
heavy damping of the meter movement for transit
purposes.
PROTECTION
The circuit incorporates a 10 A fuse in series with
the 'COMMON' terminal. This fuse is fitted to give
the user increased protection should the
instrument be connected across a high energy
source while its range switches are incorrectly set.
It is most important that the integrity of this fuse
is checked before and after any measurement is
made. This is done using the instruments own
lowest resistance range.
METER REVERSAL
If a d.c. quantity is measured with a polarity in

APPLICATIONS

the opposite sense to that assumed by the
connection of the red and black test leads, the
meter pointer will try to deflect to the left.
Operation of the 'Rev MC' self-latching push-
button enables a correct reading on the scale to
be made by reversing the direction of the meter
deflection.
BATTERY AND FUSE COMPARTMENT
A special compartment to contain the batteries (to
supply power for resistance measurements) and
fuses is moulded into the rear of the case.
The Model 8mk7 is a general purpose, multi-
range, portable meter for measurement of voltage,
current and resistance. The 20 000 Ω/V sensitivity
matches the data given in most service manuals
for electronic equipment.
The instrument is suitable for general fault finding
work, installation and commissioning work and
for use in the laboratory, in both the electrical
and electronic fields.
To enhance the use and measuring capabilities of
the instrument, many accessories are available.
5