ICC Mirius, Руководство по установке

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Modbus / Gas Water Heaters
Central Control Board Major State Definitions
Table 39. Gas Central Control Board (CCB) Major State Definitions
Value Xi 1.0 State MXi State
1 Off (Standby) Off (Standby)
2 Pre-Purge Pre-Purge
3 Igniter Warmup Igniting
4 Ignition Activation Gas Valve On
5 Ignition Verification Inter-Purge
6 Inter-Purge Heating
7 Heating Post-Purge
8 Post-Purge In Fault
9 Fault
Xi 1.0 Energy Management System (EMS) Control
Xi 1.0 uses a single bit setting method. Within the EMS Mode-Status point one bit command (bit 15) sets it in EMS mode, and other
ends EMS mode. Once in EMS mode, another bit command (bit 0) enables heating another disables heating.
Once in EMS mode the EMS Mode Refresh command must be periodically issued which clears a third bit (bit 14) to maintain EMS
mode, otherwise the heater will end EMS mode and resume normal operation.
Table 40. Xi 1.0 Energy Management System (EMS) Control
Decimal Hex Value Response
3840 0x0F00 No EMS control 0 / 0x000
3841 0x0F01 Put into EMS Mode^ 49152 / 0xC000
0000 0x0000 EMS Disable heating^ 49152 / 0xC000
0001 0x0001 EMS Enable heating^ 49153 / 0xC001
3584 0x0E00 EMS Mode Refresh^ (must write within 30 seconds
or EMS mode ends.) 15 seconds or less
recommended
49152 / 0xC000 or 49153 / 0xC001 depending on
whether or not heating is enabled.
Notes:
• The start of a heating also depend on other factors like tank temperature dropping below Setpoint – Differential and External T’stat call for heat if that option is enabled.
• Depending on when you poll the register, you may read bit 14 as 1 which is why a “C” (in hexadecimal form) might briefly reply with “8”. This is due to the control setting
this bit and if it not cleared periodically by the BACnet command, heating is disabled.
• After disabling EMS mode with write of 3840, read back might have bits 14 and 1 possibly still set. To make sure these bits are clear, write a 0000 to clear bit 1 and 3584
to clear bit 14.
Mxi Energy Management System (EMS) Control
Mxi EMS control is written as a single command to place in EMS mode and enable or disable heating.
Once in EMS mode the EMS Mode Refresh command must be periodically issued to maintain EMS mode, otherwise the heater will end
EMS mode and resume normal operation.
Table 41. Mxi Energy Management System (EMS) Control
Decimal Hex Value Response
0 0x0000 No EMS control~ 0 / 0x000
32768 0x8000 EMS Disable Heating^ 49152 / 0xC000
32769 0x8001 EMS Enable Heating^* 49153 / 0xC001
Notes:
~ For Versions less than 3.16, once EMS control mode is enabled it remains enabled through BACnet it will remain in EMS control mode that cannot be cleared by writing
a 0 to it. Power cycling only can clear EMS mode.
^ Depending on when you poll the register, you may read bit 14 as 1 which is why a “C” (in hexadecimal form) might briefly reply with “8”. This is due to the control setting
this bit and if it not cleared periodically by the BACnet command, heating is disabled.
* EMS command to heat must be sent every 30 maximum or heating will be disabled.