User guide

ENTEGRIS, INC. Customer Service Tel. [phone] Customer Service Fax [phone]
NT® INTEGRATED FLOW CONTROLLER WITH DEVICENET™ COMMUNICATION USER GUIDE
1. Flow reading is
very low.
2. Flow reading
above zero when
set point is zero
and no flow is
present.
3. Flow output is
extremely noisy
4. Unit resets.
5. Flow output does
not correspond to
set point for high
flow rates.
The unit is installed
backwards.
Insufficient line pressure.
The unit needs to be
re-zeroed.
The actual fluid flow
conditions are noisy.
The supply power
(+24V) is noisy.
Inlet pressure is not 10 PSIG
(69 kPa) greater than the
outlet pressure at the high
flow conditions.
Install the unit so the inlet flow
is plumbed on the same side as
the electrical connection.
The inlet pressure must be at
least 10 PSIG (69 kPa) greater
than the outlet pressure. Verify
the inlet pressure using the pres-
sure signal from the flow con-
troller.
Perform a zero adjust service or
enable the autozero function.
Flow turbulence may be caused
by “noisy” pumps used in a
system. Examples of noisy
pumps are diaphragm pumps
without pulsation dampeners
and peristaltic pumps operating
at low flow rates. Please contact
Entegris for additional informa-
tion.
If the power supply is shared
with other systems, components
such as solenoids, DC motors,
valves, etc., the unit may be re-
ceiving “dirty” power. Extreme
noise spikes will cause the unit
to reset. Connect the unit to a
separate power source.
Measure the inlet pressure. Also
measure the fluid pressure at the
outlet of the unit using a pres-
sure gauge or pressure transduc-
er. Verify the inlet pressure is at
least 10 PSIG (69 kPa) greater
than the outlet pressure.
Diagnostic Guide
SYMPTOM POSSIBLE CAUSES SUGGESTIONS
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