tekmar 509 Thermostat Installation - Manual (Page 3)

3 of 16 © 2012 D 508 - 04/12
Outdoor Sensor
An outdoor sensor can be connected to the thermostat. The temperature measured by
an outdoor sensor does not affect the ON time of the relay and is only used for display
purposes.
ACCESS LEVELS
Sequence of Operation
AIR SENSOR(S) ONLY OPERATION
When operating with only an air sensor, the ON time for the Heat relay is calculated to
satisfy the requirements of the air sensor.
SLAB SENSOR ONLY OPERATION
When operating with only a slab sensor, the ON time for the Heat relay is calculated to
satisfy the requirements of the slab sensor. The thermostat operates to maintain the slab
at the minimum slab temperature setting.
NOTE: Operating with only a slab sensor can lead to either overheating or underheating
of the space.
AIR AND SLAB SENSOR OPERATION
When operating with both air and slab sensors, the thermostat calculates an ON time for the
Heat relay to satisfy the slab sensor’s requirements and an ON time to satisfy the air sensor’s
requirements. The Heat relay operates for the longer of these two ON times.
During light heating loads, overheating can occur due to the minimum slab temperature
requirements.
During heavy heating loads, the maximum slab temperature setting limits the ON time of
the Heat relay. In this situation, underheating can occur.
The 508 thermostat has two access levels.
These access levels restrict the number of items
available in the menus of the thermostat. The
two access levels are User and Installer. This
selection is made using the DIP switch located
on the circuit board inside the thermostat.
Installer access level - allows the installer
to adjust all of the settings in the thermostat
including those required to match the thermostat
to the mechanical system and the devices
used.
User access level - allows the end user
to adjust the temperatures used by the
thermostat.
NO
POWER
2
Sensor
1
24 V ±10% 50/60 Hz 1.5 VA.
24 V (ac) 2 A Class 2
Installer
Access level
Not used
Power:
Relay:
For 3 wires,
install jumper
R to Rh
944-02
Thermostat 508
One Stage Heat
508
46
5
3
Rh
R
CW
User
Meets Class B:
Canadian ICES
FCC Part 15
Made in
Canada
Apr 2010
Lot 1234
1
2
ON
24 V
Dip Switch
Set to User access level once installation and settings have been completed.
Note: DIP switch 2 is not used.