38
39
resistance
of
the
opposite
line
,
and
then
divided
by2
.
Ground
resistance
value
of
other
two
reference
ground
bodies
are
:
RB
=
R1
-
RA
RC
=
R3
-
RA
X
On
-
site
Application
1
Application
of
Power
System
(
1
).
Measurement
of
the
power
line
tower
ground
resistance
Generally
,
the
power
line
tower
ground
form
into
multi
-
point
ground
system
and
clamp
on
the
ground
down
lead
by
UNIT
series
clamp
meter
,
the
ground
resistance
value
of
the
branch
circuit
could
be
measured
.
(
2
).
Measurement
of
transformer
neutral
point
ground
resistance
In
measuring
the
transformer
neutral
point
ground
resistance
,
if
data
fluctuates
greatly
,
power
off
and
test
.
There
are
two
circumstances
for
the
transformer
neutral
point
ground
:
form
into
multi
-
point
ground
system
if
repetitive
ground
exists
;
single
point
ground
measurement
if
no
repetitive
ground
.
In
measurement
,
if
clamp
meter
display
L
0
.
01
it
is
possible
that
more
than
2
ground
down
leads
of
the
same
tower
or
transformer
are
connected
underground
.
It
is
need
to
maintain
only
one
ground
down
lead
,
and
unfasten
others
.
(
3
).
Application
of
power
plant
and
substation
UNIT
series
clamp
meter
can
test
the
loop
contact
and
connect
condition
and
can
measure
the
connection
between
equipment
in
the
station
with
the
ground
net
by
a
test
line
.
The
ground
resistance
could
be
measured
as
the
single
point
ground
.
2
Application
of
Telecommunication
System
(
1
).
Ground
resistance
measurement
of
the
floor
computer
room
The
computer
room
of
the
telecommunication
system
is
always
established
on
the
upper
floor
of
building
,
difficult
to
measure
by
tramegger
.
While
it
is
quite
easy
for
UNIT
series
clamp
meter
to
test
,
just
connecting
a
test
line
with
fire
hydrant
and
the
ground
polarity
being
measured
(
each
computer
room
is
equipped
with
fire
hydrant
)
and
measuring
the
test
line
with
clamp
meter
.
Clamp
resistance
value
=
computer
room
ground
resistance
+
test
line
UT276A
/
278A
OPERATING
MANUAL
UT276A
/
278A
OPERATING
MANUAL
Summary of Contents for UT276A
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