IM 01C25T01-01E
3-17
3. OPERATION
(2) Full Sensor Trim—Auto Trim and Manual
Trim
Full sensor trim is carried out with a series of the
procedure of
Auto, Lower Pt
and
Auto, Upper Pt
.
Also, you can manually perform the trimming proce-
dure in
Manual, Lower Pt
and
Manual, Upper Pt
.
The full sensor trim is a two-point adjustment, and the
lower point adjustment should always be performed
before the upper point adjustment in order to maintain
the pitch between the zero and 100% points within the
calibration range.
In the manual method, the reference pressure should
also be applied to the transmitter at both lower and
upper point of trim ends. Without the reference
pressure,
P LTD
and
P UTD
may not represent the
correct value of adjustment point for each.
a. Auto Sensor Trim
Apply a standard pressure of 1000
mmH
2
O to the transmitter. After
obtaining a stable pressure, press
ENTER (F4)
.
Example:
For the range of 1000 to 3000 mmH
2
O
F0329.EPS
1
EJX:YOKOGAWA
Select trim mode
1 Off
2 Auto, Lower Pt
3 Auto, Upper Pt
4 Manual, Lower Pt
5 Manual, Upper Pt
ABORT ENTER
Select
Auto , Lower Pt
, and press
ENTER (F4)
.
(ENTER)
2
EJX:YOKOGAWA
Pres for trim 994.0
Auto, Lower Pt
1000.000000
1000
ABORT
DEL
ENTER
(ENTER)
‘1000’
Apply a standard pressure of 3000
mmH
2
O to the transmitter. After
obtaining a stable pressure, press
ENTER (F4)
.
3
EJX:YOKOGAWA
Select trim mode
1 Off
2 Auto, Lower Pt
3 Auto, Upper Pt
4 Manual, Lower Pt
5 Manual, Upper Pt
ABORT ENTER
Select
Auto, Upper Pt
, and press
ENTER (F4)
.
(ENTER)
4
EJX:YOKOGAWA
Pres for trim 3015.0
Auto, Upper Pt
3000.000000
3000
ABORT
DEL
ENTER
(ENTER)
‘3000’
1. Device setup
2. Diag/Service
3. Calibration
3. Pres sensor trim
2. Pres Trim
×
2
b. Manual Sensor Trim
Suppose that a standard pressure of 1000 mmH
2
O is
applied and the value of the Pres for Trim in is 994.0.
Correct for this output error of 6 mmH
2
O by adding 6
mmH
2
O to
P LTD
.
4.0
"
6.0
#"
2.0
Enter the correction value of 2.
Then press
ENTER (F4)
.
Suppose that a standard pressure of 3000 mmH
2
O is
applied and the value of the Pres for Trim in is 3015.0.
Firstly, obtain the slope error for the span as follows;
Then correct for this slope error of
10 by adding
10 to
P UTD
.
3.0
"
(
10.0)
#
13.0
F0348.EPS
1
EJX:YOKOGAWA
Select trim mode
1 Off
2 Auto, Lower Pt
3 Auto, Upper Pt
4 Manual, Lower Pt
5 Manual, Upper Pt
ABORT ENTER
Select
Manual, Lower Pt
, and
press
ENTER (F4)
.
(ENTER)
2
2
EJX:YOKOGAWA
Pres for trim 994.0
Manual, Lower Pt
4.000000
2
ABORT
DEL
ENTER
(ENTER)
‘2’
Enter the correction value of
13.
Then press
ENTER (F4)
.
3
EJX:YOKOGAWA
Select trim mode
1 Off
2 Auto, Lower Pt
3 Auto, Upper Pt
4 Manual, Lower Pt
5 Manual, Upper Pt
ABORT ENTER
Select
Manual, Upper Pt
, and press
ENTER (F4)
.
(ENTER)
4
4
EJX:YOKOGAWA
Pres for trim 3015.0
Manual, Upper Pt
3.000000
13
ABORT
DEL
ENTER
(ENTER)
‘
13’
1. Device setup
2. Diag/Service
3. Calibration
3. Pres sensor trim
2. Pres Trim
Example:
For the range of 1000 to 3000 mmH
2
O
P LTD
=
4.0 mmH
2
O
P UTD
=
3.0 mmH
2
O
Applied Pressure Value
Value of Pres for Trim
Applied Pressure Value
Slope Error
!
(URV
LRV)
#
3000
3015
3000
!
(3000
1000)
#
#
10
×
3
×
4
