Performing Instrument Calibration; Adjustable Differential - Robertshaw 5318B Instruction Manual

MODEL 5318B
Level Tek II, Capacitance Level Switch
Pressing the [RT] pushbutton will allow the time
delay to be changed. The display will initially
show:
AlarmDly
XX*
Where XX* represents the current time delay
setting. After a short time the top line of the
display will begin scrolling the message:
"Relay delay when alarm goes OFF
[seconds]"
The [UP] and [DN] pushbuttons can be used to
scroll among the possible values. The current
time delay is identified by an "*" appended to the
end of the format. When the desired time delay
value is displayed press the [RT] pushbutton to
select that value. The display will return to the
previous level of the Setup menu.
4.5. Performing Instrument
Calibration
Once the instrument has been setup the next
step is calibrate the instrument to the
vessel/process. The Model 5318B provides for
several calibration procedures. Some of the
procedures require varying the level in the
vessel, while others do not. These calibration
procedures are as follows:
•
Adjustable Differential – this
procedure is typically used when the
level difference or deadband between
the high and low setpoints on vertically
mounted probe is desired. Typically
used for applications involving motor or
pump control.
•
+ +
Alarm – Used to provide single
point control. This procedure allows
high setpoint calibration when the
current level is below the desired
setpoint. This procedure is typically
used with high dielectric materials and a
horizontally mounted probe.
•
+
Alarm – Same as the procedure
above except for use with a low
dielectric material.
•
-
Alarm
control. This procedure allows low
setpoint calibration when the current
level is above the desired setpoint. This
procedure is typically used with low
dielectric materials and a horizontally
mounted probe.
•
- -
Alarm
above except for use with a High
dielectric material.
•
Control – Used to set a single setpoint
on a probe. This procedure is typically
used with a vertically mounted probe.
All of these procedures involve a fixed
differential, except Adjustable Differential.
Once the applicable calibration procedure has
been selected the calibration is performed using
the appropriate description below.
4.5.1.

ADJUSTABLE DIFFERENTIAL

This procedure requires physically varying the
level in the vessel. This procedure is begun with
the level in the vessel at any level.
CAUTION: UTILIZATION OF THESE
CONTROLS REQUIRES THE REMOVAL OF
THE COVER. REMOVING THE COVER
VIOLATES THE EXPLOSION-PROOF RATING
OF THE ENCLOSURE
To access this calibration procedure you must
first be sure that the instrument's LCD display is
in the normal mode. This can be confirmed by
pressing the [LT] pushbutton until the normal
display is reached.
To reach the Calibration menu first press the
[DN] pushbutton twice, followed by pressing the
[RT] pushbutton once. The display will now
show:
The bottom line will be scrolling the following
message:
"Select method of setpoint
Page 11
INSTRUCTION MANUAL
909GF295
– Used to provide single point
– Same as the procedure
Step 1 RT
calibration"