Input Registers; Holding Registers; Confi Guration Bits - Lochinvar Knight 81 Instructions Manual

4
ModBus Memory Map
Memory Map
Address
30001 Discrete Inputs 1 - 16
30002 Discrete Inputs 17 - 32
30003 Discrete Inputs 33 - 48
30004 System / Cascade Setpoint
30005 System Pump Speed
30006 Cascade Total Power
30007 Cascade Current Power
30008 Outlet Setpoint
30009 Outlet Temperature
30010 Inlet Temperature
30011 Flue Temperature
30012 Firing Rate
30013 Boiler Pump Speed
30014 Boiler Status Code
30015 Boiler Blocking Code
30016 Boiler Lockout Code
40001 Confi guration
40002 Coils
0-10 Volt Input / Rate Command / Setpoint
40003
Command
40004 Tank Setpoint
40005 Tank Temperature
40006 Outdoor Temperature
40007 System Supply Temperature
40008 DHW Recirculation Temperature
Confi guration Bits
Address 40001 contains confi guration bits sent from the BAS to the appliance. Th ese bits tell the boiler/water heater to use its
own internal inputs, or inputs from the BAS. When a bit is set to 1, the boiler/water heater will ignore the corresponding value
contained internally, and expect the BAS to write that value into the Holding Registers. Th e confi guration bits are as follows:
Bit 0 (LSB): Boiler Enable
Bit 1: Tank Th ermostat
Bit 2: Rate Command / 10 - 10V Input / Setpoint Command
Bit 3: Tank Setpoint
12

Input Registers

Description

Holding Registers

ModBus and BACnet Communication Instructions
Default Unit
0 HEX
0 HEX
0 HEX
0 Degrees Celsius
0 %
0 %
0 %
0 Degrees Celsius
0 Degrees Celsius
0 Degrees Celsius
0 Degrees Celsius
0 %
0 %
0 HEX
0 HEX
0 HEX
0 NA
0 NA
0 %
0 Degrees Celsius
0 Degrees Celsius
0 Degrees Celsius
0 Degrees Celsius
0 Degrees Celsius
Bit 4: System Supply Temperature
Bit 5: Outdoor Temperature
Bit 6: Tank Temperature
Bit 7: System Return Temperature
Bit 8 - 15: Not Used (Default = 0)
Min. Max. Resolution
0 65535 1
0 65535 1
0 65535 1
0 130 0,5
0 100 1
100 800 1
0 800 1
0 130 0,5
0 130 0,1
-20 130 0,1
-20 130 0,1
0 100 1
0 100 1
0 65535 1
0 65535 1
0 65535 1
0 65535 1
0 65535 1
0 100 1
0 87,5 0,5
-20 130 0,1
-40 60 0,1
-20 130 0,1
-20 130 0,1