Modbus Communications (continued)
XRAM Variables
These variables can be read using Modbus
be written to using Modbus
the same "menu items" that are configured from the monitor keypad. The calibration and control
items are not accessible from the DDC system. This is for safety reasons since each room is
individually setup for maximum performance.
RPM10 Variable List
Variable Name
0
Number of Rooms
1
Devices Controlled
2
Measurements
Displayed
3
Display Average
4
Units
5
Access Codes
6
Relay 2
Configuration
7
Input 1
Configuration
8
Input 2
Configuration
9
Input 3
Configuration
10
Input 4
Configuration
11
Input 5
Configuration
12
Input 6
Configuration
®
Network/Modbus
Communications
®
command 03 Read Holding Registers. They can
®
command 06 Write Single Register. Many of these variables are
Variable
Address
Read/Write
Read
Read
Read/Write
Read
Read/Write
Read/Write
Read
Read
Read
Read
Read
Read
Read
Integer DDC system receives
1
1 Room
1
None
1
Room Status
2
Room Status and Pressure
3
All Measurements
1
1 second
2
2 seconds
3
3 seconds
4
5 seconds
5
10 seconds
6
20 seconds
7
40 seconds
1
in H
O, cfm, F
2
2
Pa, lps, C
3
3
Pa, m
/hr, C
1
Off
2
Room Mode
3
Menus
4
Room Mode and Menus
1
High Alarm
2
Negative Room Mode
3
Positive Room Mode
1
TSI Sensor
2
Pressure Transducer
4
None
1
Supply Pressure Flow
2
Supply Linear Flow
3
Supply Venturi
4
Supply Switch
7
None
1
Room 1 Door Switch
2
Room 1 Occupancy Sensor
3
None
1
Room 1 Keyswitch
3
None
6
None
75