Red Lion PAXLPV - Manual (Page 8)

Example 1 (± Display):
A differential pressure transducer has a range of ±15 PSI with a 1-6 V
output (-15 @ 1 V, +15 @ 6 V)
READOUT SPAN (Rs) = +1500 - (-1500) = 3000
SWING VOLTAGE (Vs) = 6 V (max) - 1 V (min) = 5 V
SPAN PER VOLT (Rs/Vs) = 3000 / 5 V = 600
Note: Since the display readout is limited to 1999 numerical indication, the
full READOUT SPAN of 3000 cannot be obtained during zero based span
adjustment. However, dividing both the READOUT SPAN and SWING
VOLTAGE by two, i.e. 1500 readout @ 2.5 V, allows the span adjustment
to be made for the proper transfer curve slope.
ADJUSTMENTS
Null the unit to zero readout @ 0 V per
Steps 1 to 4 of the calibration steps.
Set transfer curve slope with span
adjustments per Steps 5 and 6 to get a
readout of +1500 @ 2.5 V (SPAN PER
VOLT = 600).
Apply (-) offset per Step 7 to get a
reading of -1500 @ 1 V.
Check min. and max. extremes and tweak
if required to get desired readout @ 1 V
and 6 V per step 8. Set D.P. switch S2
and replace unit in case.
Example 2 (Positive Offset):
PAXLPV is to be calibrated to match a flow transducer whose output is 0
V @ 40 GPM and 5 V @ 650 GPM.
READOUT SPAN (Rs) = 650 - 40 = 610
SWING VOLTAGE (Vs) = 5 V (max) - 0 V (min) = 5 V
SPAN PER VOLT (Rs/Vs) = 610 / 5 V = 122
ADJUSTMENTS
Null the unit per Steps 1 to 4 of the
calibration steps.
Set the coarse and fine span adjustments
to get a readout of 610 @ 5 V (SPAN PER
VOLT = 122) per Steps 5 and 6.
Set offset to readout 40 @ 0 V per Step 7.
Check the readout @ max. (5 V) and min.
(0 V) and fine tune (tweak) as required
per Step 8.
Example 3 (Negative Slope):
A liquid level sensor puts out 1 V when a storage tank is full and 11 V
when the tank is empty. The PAXLPV is to read out 100.0 when the tank is
full and zero when the tank is empty.
READOUT SPAN (Rs) = 1000 - 0 = 1000
SWING VOLTAGE (Vs) = 1 V (max) - 11 V (min) = -10 V
SPAN PER VOLT (Rs/Vs) = 1000 / -10 V = -100
In this case, the signal voltage is reversed [Term. 3 (+) with respect to Term.
4 (-)] causing the readout to go “down” (increasingly negative) as the
negative voltage increases (hence, the negative (-) SPAN PER VOLT).
ADJUSTMENTS
Null the unit per Steps 1 to 4 of the
calibration steps.
Set the slope of the transfer curve with the
span adjustments to get a readout of -1000
@ -10V
(SPAN PER VOLT =
-100) per Steps 5 and 6.
Move the transfer curve up by applying (+)
offset per Step 7 until readout is +1000 @
-1 V.
Check extreme readings per Step 8 0
readout @ -11 V and +1000 @ -1 V. Set
D.P. switch S1 ON and replace unit in case.
6.0 A
PPLICATIONS
Red Lion Controls
20 Willow Springs Circle
York PA 17406
Tel +1 (717) 767-6511
Fax +1 (717) 764-0839
Red Lion Controls AP
Unit 101, XinAn Plaza
Building 13, No.99 Tianzhou Road
ShangHai, P.R. China 200223
Tel +86 21 6113-3688
Fax +86 21 6113-3683
Red Lion Controls BV
Printerweg 10
NL - 3821 AD Amersfoort
Tel +31 (0) 334 723 225
Fax +31 (0) 334 893 793