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Title: Functional description S4965V3250
6. Modes of operation
The controller has a number of basic modes of operation (from lowest to highest priority):
STAND-BY, when there is no heat demand or error present;
HEATING MODE, when high voltage heat demand input is closed;
Modbus HD MODE, when external command heat demand is received;
TEST MODE, when external Test Mode heat demand is given;
ERROR/FAULT conditions like over temperature conditions, etc.
6.1 - Start Up
After Power On, or manual reset the controller will perform check on safety features (during start-up routines) or
12/24 hours check (not a complete start up routine) depends on whether a heat demand is present:
-
When no heat demand is present the control will perform a reset 12 hours after the last one;
-
When a heat demand is present, the control will wait until a maximum of 24 hours to perform the reset.
6.2 - Stand-by
In Stand-by mode igniter is off, gas valve is closed and fan is off if fan overrun time is finished and Continuous Fan option is
switched off.
6.3 - Heating Mode
The Normal Heating mode is started when the High Voltage Heat Demand input is closed. When ignition is successful, the
fan can be controlled in a number of ways depending on parameter setting:
0-10 V control, a DC voltage between zero and ten volts can be applied to connector X3, pins 8 & 16.
At zero volt the Fan will run on minimum fan speed. At ten volt the Fan will run on maximum fan speed.
4-20 mA control, with an external resistor of 500 1 % placed between connector X3 pins 8 & 16, the fan speed
can be controlled with a current in the range of 4 to 20 mA.
At 4 mA the Fan will run on minimum fan speed. At 20 mA the Fan will run at maximum fan speed.
On/Off control, when the option On/Off control is selected, the fan speed depends on the fan slope control
parameter. When slope control is off (parameter set to zero), the fan speed will immediately go to maximum.
Otherwise the fan speed will rise from ignition fan speed to maximum fan speed with (value)*50 RPM/sec.
6.4 - Modbus HD Mode
The heating mode is started immediately when a special command receives by external communication.
Name
Modbus HD Mode
Power control
The Low byte 0xCC of first message represents this command and second message Low byte defines the power level.
The fan can be controlled between minimum and maximum fan speed by setting a between 0 and 100 % (hexadecimal
representation 0x00 – 0x64).
The messages should be repeated at least every 30 seconds to signify none break the burning process. Others way the
Modbus HD is stopped.
After the Normal Heating Mode or the Modbus HD Mode is served, post ventilation is performed, based on parameters
value fan speed and time duration. If speed is setup to zero and timer extends none zero value it's used last rate of fan
rotation in this phase.
First issue.
SW update and add parameter into list ModBus communication.
Function
ID (decimal)
(hex)
0x06
0x06
Description
Heating & Cooling Appliance Controls
Value (hex)
High byte
512
Not used
513
Not used
Sign.
I.Mariscak
I.Mariscak
Honeywell
Doc.: S4965V3250E20
Notes
Low byte
0xCC
Heat demand: ON
0x00
Heat demand: OFF
0x00-0x64
Fan speed
E.C.N.
Date
0131527
27-Jun-2016
03-Aug-2016
Rev.
A
B
Page 18/33
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