Super Systems 20PQ - Manual (Page 154)

150
AUXILIARY POWER SUPPLY
Type:
24 V DC + 20% not isolated.
Max. current: 25 mA.
SERIAL INTERFACE
Types:
RS 485 isolated
Protocol type: MODBUS, JBUS.
Baud rate: programmable from 600 to 19200 BAUD.
Byte format: 8 bit.
Parity: even, odd or none programmable.
Stop bit: one.
Address: from 1 to 255.
Output voltage levels: according to EIA standard.
NOTE: The EIA standard establishes that by RS-485 interface it
is possible to connect up to 30 devices with one remote master
unit.
The serial interface of these instruments is based on “High input
impedance” transceivers; this solution allows you to connect up
to 127 devices (based on the same transceiver type) with one
remote master unit.
MAINTENANCE
1) REMOVE POWER FROM THE POWER SUPPLY TERMI-
NALS AND FROM RELAY OUTPUT TERMINALS
2) Remove the instrument from case.
3) Using a vacuum cleaner or a compressed air jet (max. 3 kg/
cm 2 ) remove all deposit of dust and dirt which may be present
on the louvres and on the internal circuits trying to be careful
for not damage the electronic components.
4) To clean external plastic or rubber parts use only a cloth
moistened with:
- Ethyl Alcohol (pure or denatured) [C
2
H
5
OH] or
- Isopropil Alcohol (pure or denatured) [(CH
3
)
2
CHOH] or
- Water (H
2
O)
5) Verify that there are no loose terminals.
6) Before re-inserting the instrument in its case, be sure that it is
perfectly dry.
7) re-insert the instrument and turn it ON.
XKP-1-C2.p65 10/30/01, 9:37 AM 150