Section 8 Methods For Scaling The Meter To Display In - Omega DP461-S User Manual

8. Methods for Scaling the Meter to
Display in Engineering Units
8.1 INTRODUCTION
This section is for scaling the meter to read in desired engineering
units. This meter is capable of producing any engineering units up
to 6 digits regardless of decimal point. Even though this is a strain
gauge input meter it is capable of working with high voltage, current
and potentiometric inputs. The difference between strain gauge
input and a voltage input is ratiometric versus non-ratiometric
inputs. A strain gauge based sensor is ratiometric which means its
output is directly proportional to the supply voltage powering it.
Most millivolt sensors are ratiometric (strain gauge input)
The decimal point is completely programmable.
Performing the following steps will ensure that the meter is prop-
erly scaled.
1. Make sure that all jumpers are in their correct location(s). (Refer
to Section 6)
2. Provide AC power to the instrument (Refer to Section 7.3)
3. Check with a multimeter that the proper sensor excitation exists.
4. Wire the sensor to the meter (Refer to Section 7.2)
5. Program the unit for the desired display with strain gauge inputs
(Bridge inputs, refer to Section 8.2), Voltage inputs (Refer to
Section 8.3), Current inputs (Refer to section 8.4), or Potenti-
ometer inputs (Refer to Section 8.5).
8.2 STRAIN GAUGE (BRIDGE) INPUT, PROGRAMMING THE
METER FOR A DESIRED DISPLAY
An easy way to program your unit is to follow the example and step
by step procedure below and just modify it for your exact require-
ments.
EXAMPLE: An end user wants to scale the meter for a 200 PSI,
0-100 mV voltage output, pressure transducer. You want the meter
to display in hundreds of a PSI from 0 to 200.0 PSI. The pressure
sensor requires 10 Vdc excitation power.
8-1
8
Scaling to
Display
Engineering
Units