TM
11-6625-2981-14
GENERAL
INFORMATION
AND
SAFETY
PRECAUTIONS
SAFETY
PRECAUTIONS.
and
insulation
quality
tests
of
The
ohmmeter
generates
dangerous
motors,
cables,
and
electrical
voltages.
Observe
warnings.
devices.
INTRODUCTION.
RELATIONSHIP
OF
UNITS.
This
manual
covers
the
operation;
(See
The
ohmmeter
is
servicing,
and
maintenance
for
the
a
portable
self-contained
unit.
It
ZM-21C/U
The
ZM-21C/U
has
a
removable
case
for
service
ohmmeter
is
used
to
determine
the
access.
of
electric
circuits
and
equipment.
REFERENCE
DATA.
lists
the
reference
data
EQUIPMENT
DESCRIPTION.
for
the
ohmmeter.
The
ohmmeter
is
the
hand-driven
type
enclosed
in
a
metal
EQUIPMENT,
ACCESSORIES
AND
case.
It
measures
leakage
DOCUMENTS
SUPPLIED.
of
electrical
circuits
from
0
to
1000
lists
the
equipment
and
Megohms.
Typical
uses
are
breakdown
documents
supplied.
Reference
Data
Item
Data
Manufacturer
Aul
Instruments,
Inc.
(Code
25778)
Manufacturer's
Part
No.
102282
Type
Designation
ZM-21C/U
Size
7"
High
X
9"
Wide
X
7"
Deep
Weight
Approximately
6
pounds
Scale
Length
3
inches
Pointer
Accuracy
Pointer
indicates
within
2
percent
of
scale
length
at
any
of
the
marked
scale
positions.
Peak
ripple
voltage
at
ohmmeter
terminals
is
not
Ripple
Voltage
more
than
10%
of
the
effective
voltage.
500
Volts
DC
No
Load
Voltage
has
sufficient
magnetic
shielding
so
External
Field
Influence
that
the
effect
of
an
external
magnetic
field
of
5
oersteds
will
not
cause
a
change
in
indication
greater
than
1.5%
at
any
point
on
the
scale
between
0
and
40
Megohms.
Ohmmeter
will
withstand
a
voltage
of
1000
Volts
Dielectric
Strength
DC
without
damage
or
flash-over.
-15C
to
+55C
Operating
Temperature
-55C
to
+71C
Storage
Temperature
Up
to
100%
Humidity
0
to
1000
Megohms
Range
