Indicator N1500
NOVUS AUTOMATION
3/7
PROCESS VARIABLE RETRANSMISSION
As an option, the indicator can be supplied with an isolated 0-20 mA
or 4-20 mA analog output for Process Variable (PV) retransmission.
The PV values that define the scale of the 0 mA / 4 mA to 20 mA
retransmission can be programmed by the user in the high and low
output limits (
0v.lol
e
0v.kol
), at configuration level. High and
low limits can be freely programmed, even with a low limit higher than
high limit, resulting in a reversed retransmission signal (decreasing
signal when PV increases).
When this option is available, retransmission will be always active, so
that the user will not be required to turn it on or off.
For a voltage output signal an external shunt (calibrated resistor)
should be installed at the analog output terminals.
AUXILIARY 24 VDC POWER SUPPLY – AUXILIARY P.S.
The indicator provides a voltage power supply of 24 Vdc to excite
field transmitters with 25 mA current capacity. Available at the back
panel terminals 16 and 17.
CUSTOMIZED LINEARIZATION.
Three types of signals can be user-customized to fit particular
linearization profiles. This means that the operator can configure the
instrument to read non-standard crescent non-linear signals with high
accuracy.
INSTALLATION
The indicator is designed to be panel mounted. Remove the two plastic
fixing clamps from the instrument, insert the unit into the panel cut-out
and slide firmly the fixing clamps from the rear against the panel.
RECOMMENDATIONS FOR INSTALLATION
•
Input signal wires should be laid out away from power lines and
preferably inside grounded conduits.
•
Instrument mains (line) supply should be suitable for this purpose
and should not be shared.
•
In controlling and monitoring applications, possible consequences
of any system failure must be considered in advance. The internal
alarm relay does not warrant total protection.
•
Use of RC filters (47 R and 100 nF, serial) are highly
recommended when driving solenoids, contactor coils or other
inductive loads.
ELECTRICAL CONNECTIONS
The internal electronics can be removed from the front panel without
any cable disassembly. The input signals and power connections are
shown in Fig. 1.
Fig. 1 – Back Panel Terminals
POWER CONNECTION
Fig. 2 – Power Connection
SENSOR AND INPUT SIGNAL CONNECTIONS
These connections should be properly done and terminals must be
well tightened. Thermocouples must be installed with proper
extension or compensation cables.
Pt100 RTDs must be 3-wire connected and the wires connected to
terminals 22 and 23 should have the same electrical resistance
(same wire gauge) for correct cable length compensation. Four-wire
RTDs can be connected by disconnecting the fourth wire. Two-wire
RTDs can be connected by shortening terminals 22 and 23 and
connecting the Pt100 to terminals 23 and 24.
The figures below show the connections relative to each type of input.
Fig. 3 – Thermocouple input
Fig. 4 – 3 wire Pt100 input
Fig. 5 – Voltage input
Fig. 6 – Current input
Fig. 7 – Connection for 0-5 V or 0-
10 V
Fig. 8 – Digital Input
Fig. 10 shows the connections for a 4-20 mA transmitter powered by
the 24 V power supply of the indicator.
Fig. 9 – Two-wire transmitter with internal power supply
DIGITAL INPUT (DIG IN)
The digital input is activated by connecting a switch (or equivalent) to
its terminals, as shown in Fig. 8 above.
ANALOG OUTPUT
The N1500 can deliver either 0-20 mA or 4-20 mA analog output,
depending on how the instrument is configured. The output is
available at terminals 29 and 30.
