Rev
A2
LC900007
17
of
18
EXERCISE
(continued)
Step
Ten
The
following
exercise
demonstrates
inventory
control
with
a
high
and
low
level
alarm.
The
usable
range
is
between
16
and
56
inches
of
liquid.
The
high
level
alarm
occurs
at
50
inches
of
liquid
and
the
low
level
alarm
occurs
at
20"
of
liquid.
Enter
all
values
into
the
LC52
in
inches.
The
OFFSET
is
the
corresponding
4mA
setting
in
inches.
The
SPAN
is
the
corresponding
20mA
setting
in
inches.
RLY1
is
dedicated
to
the
high
level
alarm
because
it
is
a
single
set
point
relay.
RLY2A
is
dedicated
to
the
low
level
alarm
because
the
latch
is
turned
off
on
Relay
2.
Use
the
following
values
for
programming
the
LC52
‐
1001.
OFFSET
16.0
SPAN
56.0
RLY
1
50.0
RLY
2A
20.0
RLY
2B
N/A
The
next
exercise
demonstrates
the
same
inventory
control
with
a
high
and
low
level
alarm.
However,
the
units
have
been
changes
from
inches
to
gallons.
Along
the
straight
side
of
the
tank,
1”
=
50
gallons
of
liquid.
The
usable
range
is
now
from
50
to
250
gallons
of
liquid.
The
high
level
alarm
occurs
at
220
gallons
of
liquid.
The
low
level
alarm
occurs
at
70
gallons
of
liquid.
Enter
all
values
into
the
LC52
in
gallons.
The
OFFSET
is
the
corresponding
4mA
setting
in
gallons.
The
SPAN
is
the
corresponding
20mA
setting
in
gallons.
RLY1
is
dedicated
to
the
high
level
alarm
because
it
is
a
single
set
point
relay.
RLY2A
is
dedicated
to
the
low
level
alarm
because
the
latch
is
turned
off
on
Relay
2.
Use
the
following
values
for
programming
the
LC52
‐
1001.
OFFSET
0
SPAN
250
RLY
1
220
RLY
2A
70
RLY
2B
N/A