User guide

NT® INTEGRATED FLOW CONTROLLER WITH DEVICENET™ COMMUNICATION USER GUIDE
18 Customer Service Tel. [phone] Customer Service Fax [phone] ENTEGRIS, INC.
6. Flow rate is not
meeting desired
set point within
10 seconds or
longer.
7. Flow output is not
responsive to
changes in set
point signal.
8. Net LED flashes
green. Valve goes
to safe position,
default position is
closed.
The unit is receiving a set
point signal with no fluid
flow present. The flow con-
troller valve is moved to the
full-open position. Depending
upon flow range, the unit
may require 10–15 seconds
or more to move from the
full-open position to the
correct set point position.
Inlet pressure is not 10 PSIG
(69 kPa) greater than outlet
pressure.
Valve in full-open position.
If the unit is plumbed
between two closed valves,
the unit may stall in the full-
open position when the unit
is commanded to close.
Since a fixed volume of fluid
is incompressible, the unit
may stall when attempting
to close if upstream and
downstream valves are
closed.
Network down
Do not send a set point signal
to the unit when no fluid flow is
available.
(see above, Symptom 5)
Avoid conditions of simultane-
ously closed valves upstream
and downstream of the unit.
The unit can be returned to
normal operation by performing
a re-zero, or by cycling power.
Reconnect to network
SYMPTOM POSSIBLE CAUSES SUGGESTIONS
Diagnostic Guide (continued)
ENT48906 10/15/04 8:12 AM Page 18