Atest Gaz PW-033-A, User Manual

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dedicated digital inputs. Purpose of those inputs is exactly the same as in case of DI lines outlined in Section
2.3.
Exchange of information is carried out by means of the RS-485 digital link and MODBUS protocol, where the
control unit module operates as a SLAVE device. The mentioned functionalities are implemented as read
and write operations for registers from the address space of ‘holding registers’ in the control module. Two
options of MODBUS protocol are available:
MODBUS ASCII – transmission rate of 19,200 bauds, frame format: 7 data bits, parity bit and one
stop bit. It is the default configuration.
MODBUS RTU – transmission rate of 19,200 bauds, frame format: 8 data bits, no parity bit and one
stop bit. It is the default configuration.
The address of the control unit can be configured within the range from 1 to 255 with the default address of
20.
The map of the control unit memory is shown in Attachment [4].
The default configuration of External Data Inputs is shown in the table below.
Bit Flags Description Default configuration
0 External_DI_0 Input no. 0 Deactivation of an internal buzzer
1 External_DI_1 Input no. 1 Deactivation of an external sound warning device (siren)
2 External_DI_2 Input no. 2 Reset of a locked optic /light warning device
3 External_DI_3 Input no. 3 Activation of an alarm
4..15 External_DI_4..15 Input no. 4..15 Not assigned
Table 6: Default configuration of External DI input
The desired functionalities for that port must be specified upon submission of the order
(both the transmission protocol and assignment of External Digital Inputs to specific
functions).
The port is sensitive to polarity of transmission lines – see details in Section 2.6.
2.6 Polarity of communication lines
SBUS and ExBUS communication ports are sensitive to polarity of transmission line. To configure the desired
polarity it is necessary to gently open a lid that secures contacts of SBUS and ExBUS ports and insert
jumpers into appropriate sockets of uncovered terminals.
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User Manual: POD-002-ENG R03
Figure 9: Jumpers to set polarity of SBUS and ExBUS ports, available after removing of the protection lid
SBUS port
Jumpers for polarity
of ExBUS port
ExBUS port
Jumpers for polarity
of SBUS port