Avid Technology SMARTCAL, Installation And Operation Manual

Page: 28 / 55

CRANE CO.
280 N. MIDLAND AVE., STE 258, SADDLE BROOK, NJ 07663 WWW.AVIDCONTROLS.COM
12/17/12 TECH-440/D.W.O. 23135 Page 28 of 55
positioner is set-up on a new application and only if the
ACAL
routine is not
performed.
Trnd
The purpose of this function is to calibrate the positioner’s pressure transducer.
It should be performed only after a manual sensor calibration.
mA
This routine calibrates the positioner’s electronics to recognizing input current.
This is done using 4.0 mA and 20.0 mA as reference points. If exactly 4.0 mA or
20.0 mA cannot be given as inputs, the user can adjust the positioner’s values to
the input using the arrow buttons.
Xmr
This routine calibrates the positioner’s optional 4-20mA position transmitter. The
transmitter calibration does not require the user to change the input current,
although it does require the user to be able to read the transmitter’s value in mA.
For each, the zero and span, the user is first prompted to enter the value that the
transmitter is presently at. This is done by using the up and down arrow buttons.
The user is then prompted to enter the desired transmitter output (typically 4.0
mA for zero and 20.0 mA for span). The positioner then calculates the difference
between the present and the desired output currents (for zero and span) and
uses the differential to adjust the transmitter accordingly.
Flow
This function allows for the setting of the flow characteristic of the positioner (not
to be confused with the flow characteristic of the valve). The options are
Lin
(Linear)
,
EP (Equal Percentage)
and
Opn (Quick Opening)
. A
Lin (Linear)
positioner characteristic duplicates the inherent characteristic of the valve and is
the most often used setting.
Type
This function configures the positioner for the type of
valve. The options are
R (Rotary)
and
L (Linear)
.
This setting needs to be done in order to configure
the positioner to recognize the type of magnetic
feedback being given to the positioner. This setting is shown on the left side of
the LCD.
FLOP
This function allows the user to configure the positioner to match the failure
method of the valve/actuator. The options are
“off”
or
“on”
. The
“off”
option is
for fail closed applications and the “on” option is for fail
open application. When
“off”
is chosen the LCD will
read 0% at the
zero (Lo Calibration)
and 100% at the
span (Hi Calibration)
. When
“on”
is chosen the LCD
will read 100% at the
zero (Lo Calibration)
and 0% at
the
span (Hi Calibration)
.