tekmar

XP Version

This driver controls tekmar thermostats over RS-232 via the tN4 Gateway 482. It was built and tested using a 482 as well as 546 and 538 thermostats in a system including a Reset Module 423 and a Dual Zone Manager 337.

The adapter provided with the 482 mates directly with the RTI RJS-232

IMPORTANT: The tekmat HVAC system is a sophisticated building control system and successful integration requires extensive knowledge. If you have never used tekmar before you will need the help of the tekmar installer to understand its set up and operation.

The address shown on the thermostat is rarely the address entered into the driver.

Revision History
1.0 The original release of the driver
1.01 Fixes an error adjusting setpoints in Celsius

Important Notes

While the connection between the 482 and XP processor is fairly fast, the baud rate of the tekmar buss is extrememly slow. As a consequence there can be a considerable lag between the time changes are made in one system and the time they actually show up on the other. In addition, at power up it can take several minutes for the initial thermostat variable data to show up on the RTI panel.

The Active Demand mode (and it's variable) are decoupled from the actual thermostats request for control of the room, particularily when using slab setpoints. It is possible for the H1 etc indicators on the thermostat to be on, while the active demand is off.

Configuration

The temperature units (C or F) can be set by a pull down menu on the driver display tab of the processor page in ID

Thermostat Address Mapping

Also on the driver tab is a list of all the thermostats in the system. The driver supports up to 32 thermostats, because of the arbitrary nature of the thermostat addresses, this section maps the tN4 addresses of the stats into the variable space of the driver Included with the .zip file when you downloaded the driver is a document from tekmar that explains the thermostat addressing system.