Operating Manual
82
Arc fault
protection ZŁ-4A; (07.2019)
14. Communication ports
Communication among elements of ZŁ-4A system is realized by CAN bus. CAN bus is
highly resistant to any disturbances. It possesses low level for EMI emission and also has the
high-speed transmission.
Furthermore, the central unit has an isolated galvanic RS485 connection. RS485 connec-
tion can service MODBUS RTU protocol, which can be used for communication with a supe-
rior system.
14.1. CAN bus
There is a two-wire network with CAN 2.0A (ISO 11898-2:
High Speed CAN Bus
)
implemented in ZŁ-4A protection (version 2.0B is not serviced).
Communication protocol has been developed as a company protocol dedicated to ZŁ-4A
devices group with the possibility to be expanded in the future for new devices.
The network can be composed of maximum 99 bay units (JP), 5 executive units (JW) and
one central unit (JC). Every network element (JP, JW or JC) has two numbers:
•
16-bit, unique serial number set by the producer (
ProductID
); that number is recorded
in microprocessor, which controls the device; the serial number is written on the rat-
ing plate;
•
8-bit number of the network node, that is the physical address (
NodeID)
.
The factory setting of the transmission speed is 250 kbit/s. The maximum length of the
CAN bus is 250m.
14.2. RS485 Interface
The central unit is equipped with RS485 communication interface, with the following pa-
rameters:
Transmission mode
differential voltage signaling
Type of transmission line
twisted-pair
Transmission Speed
Word length
Parity
Stop bits
Up to 57 600 bps
19 200 bps (factory settings)
8
No
1
Maximum length of the line
1 200 m
Transmitter output
min.
1,5 V (for loading 54
)
Receiver sensitivity
200 mV
Summary of Contents for ZL-4A
Page 24: ...Operating Manual 24 Arc fault protection ZŁ 4A 07 2019 Fig 5 ZŁ 4A JC dimensions ...
Page 25: ...Operating Manual Arc fault protection ZŁ 4A 07 2019 25 Fig 6 ZŁ 4A JP dimensions ...
Page 26: ...Operating Manual 26 Arc fault protection ZŁ 4A 07 2019 Fig 7 ZŁ 4A JW dimensions ...
Page 61: ...Operating Manual Arc fault protection ZŁ 4A 07 2019 61 Fig 36 Page 2 STATUS using ...