tekmar 261 Boiler Control User Manual

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Unoccupied Switch

If an external timer (tekmar Timer 032) or switch is used, connect the two wires from
the external switch to the

UnO Sw and Com terminals (13 and 14). When these two

terminals are shorted together, the control registers an unoccupied signal.

STEP FIVE

TESTING THE WIRING

Each terminal block

must be unplugged from its header on the control before power is applied for testing. To remove a terminal

block, pull it straight down from the control.

The following tests are to be performed using standard testing practices and procedures, and should only be carried out by properly
trained and experienced persons.

A good quality electrical test meter, capable of reading from at least 0 - 300 V (ac) and at least 0 - 2,000,000 Ohms, is essential to
properly test the wiring and sensors.

Test The Sensors

In order to test the sensors, the actual temperature at each sensor
location must be measured. A good quality digital thermometer with a
surface temperature probe is recommended for ease of use and
accuracy. Where a digital thermometer is not available, a spare sensor
can be strapped alongside the one to be tested, and the readings
compared. Test the sensors according to the instructions in the Data
Brochure D 070.

Test The Power Supply

Make sure exposed wires and bare terminals are not in contact with
other wires or grounded surfaces. Turn on the power and measure
the voltage between the

Power L and Power N terminals (5 and 6)

using an AC voltmeter. The reading should be between 108 and 132
V (ac).

Test The Powered Inputs

Boiler Demand

Measure the voltage between the

Boiler Demand terminals (1 and

2). When the boiler demand device calls for heat, you should
measure between 20 and 260 V (ac) at the terminals. When the
boiler demand device is off, you should measure less than 5 V (ac).

Setpoint Demand

If a setpoint demand is used, measure the voltage between the
Setpoint Demand terminals (3 and 4). When the setpoint demand
device calls for heat, you should measure between 20 and 260 V
(ac) at the terminals. When the setpoint demand device is off, you
should measure less than 5 V (ac).

Setpoint

Demand

20 to 260 V (ac)

Boiler

Demand

20 to 260 V (ac)

Power

108 to 132 V (ac)

Boil

Out

Com

Timer switch

UnO