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INSTRUCTION MANUAL 10DX3111A&G Sizes 14 - 24 Inches
(Equation #3)
where:
Q
= volumetric flow rate
A
= cross-sectional area
D
= pipe section diameter
E
= induced signal voltage
s
E
= reference voltage
r
B
= magnetic flux density
α
= dimensionless constant
β & γ = dimensional constant
V
= liquid velocity
Therefore, volumetric flow rate is directly proportional to the induced signal voltage as measured by
the ABB Automation Magnetic Flowmeter.
4.2 Operating Characteristics
4.2.1 Liquid Variables
4.2.1.1 Liquid Conductivity
The Magnetic Flowmeter requires a liquid conductivity of 5 microsiemens per centimeter or higher for
operation. This minimum liquid conductivity requirement is not affected by the length of the signal
interconnection cable when remote mounting of the Signal Converter is required, as long as the ABB
Automation supplied interconnection cable (with driven shields) is utilized. The nominal maximum
transmission distance is limited to 200 feet (60 meters); however standard cable length is 50 feet (15
m) unless otherwise specified.
The conductivity of a given liquid,
condition, as follows:
1) Remove the Converter housing cover. Disconnect the electrode signal interconnection leads
from terminals "1" and "2" of the Signal Converter. (These leads should be identified so that
they will be properly reconnected.)
2) Measure the resistance between signal leads "1" and "2" with an ac ohmmeter.
Do not use a dc ohmmeter for this measurement as polarization
Q = γ E
s
E
r
σ
, may be determined experimentally under a filled meter
CAUTION
effects will produce completely erroneous data.
4-3
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