INVUE ELECTRONIC FLOWMETER, MODEL NT4400
6
User Guide | Entegris, Inc.
ELECTRICAL INSTALLATION
—
Power Supply Requirements
The power supply for the InVue
Electronic Flowmeter, NT4400 must
provide clean power and must be
used only to power similar measure-
ment-type devices. The power supply
must not be used to power inductive
loads such as motors, relays, or sole-
noids. These devices may produce
transients that may affect the flow-
meter measurements when such an
inductive device is powered-up or
powered down.
In addition to providing clean power,
return lines must not be run within
the same conduit or cable. Heavy
current demands from motors, charg-
ing capacitors or other inductive
loads may cause a voltage change
within the instrumentation signal line,
causing erroneous output readings
from the flowmeter.
Input Power
The InVue Electronic Flowmeter,
NT4400 requires a nominal 24 VDC
(12 – 28 VDC input voltage) to
operate. Table A on page 7 describes
the unit input power requirements.
Output Signals
The InVue Electronic Flowmeter,
NT4400 provides two optically
isolated analog 4 – 20 mA output
signals, one signal for flow and
one signal for pressure. Each analog
output signal uses a standard two-
wire system that requires a 24 VDC
(12 – 28 VDC) power supply with less
than 2% ripple at 100 or 120 Hz.
The required power supply voltage
(V
PS
) for the output signal(s) varies
with the maximum load resistance,
R
Load
(see Figure 4 on page 9).
Flowmeter output signals are
described in Table A.
Input and output signals to the InVue
Electronic Flowmeter, NT4400 are
supplied through an 8-wire FEP-jack-
eted pigtail or an optional 8-wire
removable PVC-jacketed electrical
connector (D-Series connector),
located on the top of the flowmeter.
8-wire Connector (D-series Connector)
1
3
2
5
4
6
7
8
