andrews MAXXflo EVO Installation And Maintenance Manual page 38

4.10.3 COMMUNICATION CONNECTIONS
This heater has communication connections, which can be used for a Building Management System, web
server or expansion of inputs/outputs.
Modbus - Is a BMS language protocol which BMS systems can interface with, either directly or through a
gateway. Parameter values can be read and written directly to the Master controller
MODBUS SETTINGS:
Menu Parameter
Modbus 6651
Slave address
6652
Baud rate
6653
Parity
6654
Stop bit
Comments on Date and time values
Year (8 bit value)
Month
Time program
BSB (Boiler System Bus) - Is the communication system of the water heater, which is used to send and re-
ceive information from the other controllers (if fi tted) and can be used by the optional OZW672 Web Server, to
provide access to the heater via the internet or mobile phone app. Please contact Andrews Water Heaters for
further advice.
Installation
Settings
If connecting more than one device to the Modbus network, each appliance
must have its own unique slave address.
All devices in the Modbus network must have the same rate of transmission.
The higher the transmission rate the shorter the lines between the devices
has to be (doubling the baud rate halves the cable lengths).
Recommended baud rate with a cable of less than 500m length "19,200"
All devices in the Modbus network must have the same parity.
Recommended setting "Even"
All devices in the Modbus network must have the same number of stop bits
(1 or 2). If 2 stop bits are set, then parity must be set to none.
Recommended setting is "1"
2000 - 2099 = 100...199
1 = January...12 = December
Time value is in periods of 10 minutes.
Example:
Switch on time of 06:10 = H-Byte value: 37
Switch off time of 22:00 = L-Byte value: 132
38 MAXXfl o EVO