Operating instructions
SERIES 4OO
à
ADJUSTMENTS
Coniinued
Figure
6
CALIBRATION
(See
Figure
7)
Every Senes
400
Controller
is
carelully
calibrated
and tested before shipment,
but
recalibration may
be
required
to nullify offsets
resulting
from
differences
between
bench
calibration
and actual
process
measurement.
Figu¡e 7
The enti¡e
actuator assembly
(C)
can be moved to
the right
or
Ieft to inc¡ease
or decrease, respectively,
the rate
of
travel
of the
indicating
pointer.
This is
done
by loosening
screws
(A)
anO
(B).
Adiustment
of
nut
(E),
after
loosening
locknut
(D),
raises
or
Iowers
the entrre
bellows
by a
fixed amount.
To
calibrate
the
controller,
use
one of
the followÍng
methods:
Method
1
(When
the
controller
is
normally used
within
a narrow
range
of temperatures)
1.
With the
process (or
calibration
bath)
at
the
desired
temperature,
loosen
locknut
(D).
2. Adjust
nut
(E)until
the
indicating
pointeragrees
with the
process
temperature.
3. Tighten
locknut
(D).
Method 2
(For
maximum
calibration
accuracy over
the
full temperature range)
1. With the
process
temperature
(or
calibration
bath)
near the center of the
scale
range.
loosen
locknut
(D).
2. Adjust nut
(E)until
the indicating
pointer
agrees
with
the
process
temperature,
3. Tighten locknut
(D).
4. With the
process
temperature
(or
calibration
bath) near
one
end of the scale range, loosen
screws
(A)
and
(B)and
move
the
actuator
assembly
Ieft
or
right untilthe indicating
pointer
agrees
with the
process
temperature.
5.
Repeat
steps
1
-
3
MAINTENAT{CE
LUBRICATION
No lubrication is
required.
GI.ASS REPI.ACEMENT
1. Remove broken
glass
and excess cement
2. Line'window
frame with
Dow Corntng
732
RTV
Rubber Cement.
3. Insert
glass
and
apply
light
even
pressure.
4. Allow cement
to cure
before subjecting
controller
to
vibration
or shock.
SNÀPSWITCH REPLACEMENT
Snapswitches
are unlikely to need replacement
except
when
operated
in
a short
ci¡cuit or
continuously in a
contamtnated atmosphere.
The
procedures
for
replacing snapswitches
are
as
tollows:
In
Standard Housing
(See
Figure 8)
1. Remove
top cover.
2. Remove switch
and mounting
bracket by
removing
screw
(A)
and
sliding switch
to the
right
(away
from screw
(B),
3, If the switch wili not
easily slide
away from
screw
(B),
reduce compression
on the
switch
by
depressing
lever
(F)
in Figure
4.
4. Insert new switch.
Ensure
that
insulation
remains intact
and
in
position.
Figure
I
t
J