Calibrating The Analog Outputs - GE DigitalFlow DF868 Service Manual

Chapter 1. Calibration

1.3 Calibrating the Analog Outputs

Every Model DF868 flowmeter includes two built-in analog outputs (A and B) at terminal block
Slot 0
designated as . Both the zero-point and full-scale values for each output must be calibrated. After calibrating the
outputs, which have a resolution of 5.0 A (0.03% full scale), their linearity should be tested.
Note: The zero point of the analog output may be set for either 0 mA or 4 mA. However, the calibration procedure
always uses the 4 mA point, as the meter will extrapolate this value to obtain the 0 mA point.
Prepare for the calibration procedure by connecting an ammeter to analog output A of
below. Refer to the menu map in Figure 6 on page 13.
[CAL]
Press the key to enter the Calibration Program:

CALIBRATION
Cal
last slot selected
SLOT0 SLOT1 SLOT2 SLOT3
2
Terminal Block I/O (Slot 0)
4
B B
RTN SIG
Figure 1: Ammeter Connection (Output A)

[F1]
Press to calibrate
installed option card.)
1
A A
RTN SIG
- +
Ammeter
Slot 0
. (The option bar will include a slot listing for each
DigitalFlow™ Multipurpose Ultrasonic Liquid Flowmeter Service Manual
I/O
, which is
Slot 0
, as shown in Figure 1