IOM / @DNOVA-µAC-0907-E - Page 9
oPtIonAL BoARDs
The µAC is designed for the application of optional boards,
depending on requirements.
- Rs485 serial board:
the µAC can be included in a supervisory
or telemaintenance network;
- clock board:
enables the clock functions, time bands and
alarm log;
- programming key:
allows the list of set parameters to
be saved and/or copied to other instruments in a quick and
reliable manner.
Rs485 serial board
In order to use the µAC in an RS485 supervisory or
telemaintenance network, the optional RS485 board must be
inserted, as follows:
- disconnect power from the µAC;
- insert the RS485 board in the relative connector on the I/O
board (see Fig. 3);
- connect the serial line, according to the polarity indicated;
- reconnect power to the µAC.
n.B.
The serial line should be terminated with a 120 ohm - 1/4W
resistor, between the Tx/Rx terminals of the RS485 board on
the µAC at the opposite end of network from the supervisor.
set up
Set the network address of the µAC using parameter Ho, and
the speed using parameter HP, where:
standard:
optically-isolated asynchronous RS485
Maximum speed:
19200 baud
Maximum number of devices:
200
Maximum distance from supervisor:
1 km
cables:
1 twisted pair and shield, AWG20/22 with capacity
between leads < 90pF/m (e.g. BELDEN 8761-8762 cables)
Protection against electric shock:
the device guarantees
only a functional insulation between the source power supply
of the µAC and the serial line, thus the µAC must power supply
must feature a safety transformer.
clock board
To enable the clock, time band and alarm log functions,
insert the MAC2CLK000 board and perform the following
procedure:
- disconnect power from the µAC;
- insert the MAC2CLK000 on the I/O board (see Fig. 3);
- reconnect power to the regulator;
- set the date and time and delete the alarm log.
HP
speed
1
1200
2
2400
3
4800
4
9600
5
19200
RS485 serial board technical specifications
Power supply:
from the µAC using plug-in connector
current consumption:
20mA
storage conditions.:
-10÷70°C, R.H. < 80% non-
condensing
operating conditions:
0÷65°C, R.H. < 80% non-
condensing
Dimensions:
46x44 mm
Index of protection:
IP00
environmental pollution:
normal
surface temperature limits:
as for operating temperatures
Classification according to protection against electric
shock:
to be integrated in Class I or II devices
Category of resistance to heat and fire:
D
PtI of materials used for insulation:
250V
serial output:
3-way screw terminal connector for leads with
min. cross-section of 0.2 mm
2
and max. cross-section of 1.5
mm
2
OPTIONAL BOARDS
Serial Converter
RS 485
