3
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
30006
Cascade Total Power
30007
Cascade Current Power
30009
Outlet Temperature
30010
Inlet Temperature
30011
Flue Temperature
30012
Firing Rate
30014
Status Code
30015
Blocking Code
30016
Lockout Code
30026
Discrete Inputs 49 - 64
30027
Lockout Code Leader
30028
Lockout Code Member 1
30029
Lockout Code Member 2
30030
Lockout Code Member 3
30031
Lockout Code Member 4
30032
Lockout Code Member 5
30033
Lockout Code Member 6
30034
Lockout Code Member 7
40001
Confi guration
40002
Coils
0-10 Volt Input / Rate Command / Setpoint
40003
Command
40004
Tank Setpoint
40005
Tank Temperature
Confi guration Bits
Address 40001 contains confi guration bits sent from the BAS to the unit. Th ese bits tell the unit to use its own internal inputs,
or inputs from the BAS. When a bit is set to 1, the unit 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): Enable
Bit 1: Tank Th ermostat
Bit 2: Rate Command / 10 - 10V Input / Setpoint Command
8
Input Registers
Description
Holding Registers
Default
Unit
0
N/A
0
N/A
0
N/A
0
Degrees Celsius
0
%
0
%
0
Degrees Celsius
0
Degrees Celsius
0
Degrees Celsius
0
%
0
N/A
0
N/A
0
N/A
0
N/A
0
N/A
0
N/A
0
N/A
0
N/A
0
N/A
0
N/A
0
N/A
0
N/A
0
N/A
0
N/A
0
%
0
Degrees Celsius
0
Degrees Celsius
Bit 3: Tank Setpoint
Bit 6: Tank Temperature
Bit 8 - 15: Not Used (Default = 0)
ModBus and BACnet Instructions
Min.
Max.
Resolution
0
65535
0
65535
0
65535
0
130
0,5
100
800
0
800
0
130
0,1
-20
130
0,1
-20
130
0,1
0
100
0
65535
0
65535
0
65535
0
65535
0
65535
0
65535
0
65535
0
65535
0
65535
0
65535
0
65535
0
65535
0
65535
0
65535
0
100
0
87,5
0,5
-20
130
0,1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1