Cameron NUFLO MC-III EXP, Руководство пользователя

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MC-III™ EXP Flow Analyzer Section 3
Setting Input Type and Sensitivity
The flowmeter signal can be obtained from a magnetic pickup or a pre-amplifier device.
The input sensitivity of the MC-III EXP is measured in millivolts (mV) peak-to-peak. This is the threshold
value at which the circuitry responds to a signal. If the input signal is less than this value, the MC-III EXP will
not count the electrical pulses as a valid turbine meter signal. If the input signal is equal to or greater than this
value, the electrical pulses received at the input will be counted. Care must be taken to ensure that the input
sensitivity is high enough to reject any electrical noise on the signal line, but not so high that flowmeter pulses
are missed. The input sensitivity of the MC-III EXP may be set to low, medium, or high when the input will
be provided by a turbine flowmeter.
If the input will be provided in the form of a pulse from a pre-amplifier or other device (rather than directly
from a turbine flowmeter), the “Pulse In” (pulse input) setting in the Input Sensitivity menu should be
selected.
See
Section 2, page 13,
for input wiring diagrams.
To Set Input Type and Sensitivity:
Enter the K-Factor menu. Press K-FACTOR MENU.
K-FACTOR
MENU
Locate the input sensitivity setting. Press ENTER, repeatedly if
necessary, to bypass calibration
factor.
SAVE
ENTER
If the input is the turbine meter, select
a sensitivity setting: low, medium, or
high.
If the input is provided by a different
device, such as a pre-amplifier, select
“Pulse in” (for pulse input).
Press UP ARROW to select a
sensitivity setting.
TEST
Select low, medium,
high, or Pulse In
Press ENTER. “SAVING” will appear
in the bottom display.
SAVE
ENTER