Modbus Rtu - Honeywell HVAC232 Series Applications Manual

CHANGE OF ONE PARAMETER:
User tries to change a parameter value when password is enabled  display
PW;
Press OK button;
Cursor (lowest horizontal segment) of the very left digit flashes;
Select first digit of password by using UP and DOWN key;
Press RIGHT button;
Cursor of the second digit flashes;
Select second digit of password by using UP and DOWN key;
Press RIGHT button;
Cursor of the third digit flashes;
Select third digit of password by using UP and DOWN key;
Press RIGHT button;
Cursor of the fourth digit flashes;
Select fourth digit by using UP and DOWN key; Press OK button;
Current value of parameter to be changed will be display;
Change parameter value as normal;
Press OK --> New parameter value will be stored and Password is enabled again;
For changing another parameter the procedure has to be repeated;
In the case of wanting to change multiple parameters it is of advantage to
set P4.3 to 0000;
After the change of the parameter values password has to be activated again;
FORGOTTEN PASSWORD:
Follow procedure "Disabling a password" and select 6020 as actual password.
Application manual HVAC232/402 | Document 27-652 | Issue ENG06 | 2019-08-07

10.17 Modbus RTU

HVAC232/402 has a built-in ModbusRTU bus interface. The signal level of
the interface is in accordance with the RS-485 standard.
The built-in Modbus connection of HVAC232/402 supports the following
function codes:
Table 52. Modbus RTU
Function code Function name
03 Read
holding registers
04 Read
input registers
06 Write
single registers
16 Write
multiple registers
Address Broadcast
messages
All ID numbers No
All ID numbers No
All ID numbers Yes
All ID numbers Yes
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