Ashcroft GC52 - Rangeable wet/wet Differential Pressure Transmitter - Manual (Page 17)

17
Min. differential pressure P
1
and
max. differential pressure P
2
setting ==> Setting item
ቧ
,
ቨ
OFFSET & FULL SCALE setting ==> Setting item
ቩ
,
ቪ
,
ቫ
Display Display
Full Scale
Full Scale
(20mA)
(4mA)
Offset
(4mA)
Offset
(20mA)
Differential
Pressure Differential
Pressure
P 1
(Min.)
P 2
(Max.)
P
1
(Min.)
P 2
(Max.)
(2) Analog output
The zero point (4mA) and span point (20mA) of analog output can be
set in the range of –10 to 110%F.S. of the maximum display span (be-
tween OFFSET and FULL SCALE). The span between the zero point
and the span point in this analog output is the linear display span.
Analog output zero point
and span point setting Setting item
ቭ , ቮ
As shown in the previous diagram, usually, the OFFSET is set as Out-
put zero point (4mA) and the FULL SCALE is set as Output span point
(20mA), but the OFFSET can be reversed to Output span point
(20mA) and the FULL SCALE can be reversed to Output zero point (4mA).
Ⅵ Setting example 2 : Linear display mode
A level gauge using a differential pressure range of 0 to 200 in.H
2
O,
the linear display setting to display the OFFSET for minimum 20
in.H
2
O as 0.0, the FULL SCALE for maximum differential pressure 120
in.H
2
O as 50.0, the unit as arbitrary unit (m), the zero point (4mA) ana-
log output as 0.0, and the span point (20mA) as 50.0 is as follows:
• The setting range for the minimum differential pressure P
1
and
the maximum differential pressure P
2
is 0 to 100%F.S. of the dif-
ferential pressure range, and the maximum differential pressure P
2
is set from the value which is more than 25%F.S. of the differential
pressure range above the minimum differential pressure P
1
.
• The setting range for the OFFSET and FULL SCALE values
is –1999 to 1999, and the decimal point can be set arbitrarily. At
this time, the arbitrary unit monitor turns on
See Section 14.4 for full menu.