tekmar 650 User Manual

- Data Brochure

D 650

Snow Melting Control 650

08/10

The tekmar Snow Melting Control 650 is a microprocessor-based control that uses a Slab Sensor 072 and an Outdoor Sensor 070 (both supplied with the control) to maintain a snow melt slab at a set surface temperature during snow melting. When melting is not required, the melting system is either shut down or the slab is maintained at an idling temperature for faster response and improved safety. The melting mode is initiated manually by a button on the control or by an optional remote switch. Built in energy saving features include warm and cold weather cut offs that automatically shut the melting system down in warm weather or extremely cold conditions. The timer included in the control can be programmed to operate the snow melt system for a set time

Outdoor Slab Sensor Target Slab

Item

Time

Start Stop

Snow Melting Control 650

Pulse Width Modulation

CWCO

Idling

Melting

period. Viewing and programming the operating parameters in either °C or °F is accomplished through a digital LCD. The display indicates an error message whenever a sensor or its wiring develops a fault.

Sequence of Operation

Powering up the Control

After the Snow Melting Control 650 is powered-up, the LCD screen segments are turned on for 3 seconds. The control then monitors and displays the outdoor temperature.

Melting Mode

The Snow Melting Control 650 is a manual control; in order to start the melting system with the control powered up, the

Programming

mode

indicator

“Start” button is pushed. The melt system can also be started by setting the “Melt at power up” DIP switch to “On” and powering up the control. When the control is in melting mode, the melting pointer ﬂashes slowly and the system relay is turned on. The heat relay is cycled on and off to maintain the slab at the “Melting” temperature. The method used to cycle the heat relay is called Pulse Width Modulation (PWM). For more information on PWM, see Essay 000. Once the slab has

Item

identiﬁers

reached the “Melting” temperature, a timer starts. The control remains in melting mode until the timer “On Time” reaches zero, the “Stop” button is pushed, or the remote switch is turned off. Note: If the remote switch is turned off and on again to restart

the system, the switch must be kept off for at least 1

Item

selection

and display

button

second for the control to fully power down.

Idling Mode

When the snow melting system starts from a cold temperature, the time required for the slab to reach “Melting” temperature can be excessive. To decrease this start up time, the slab can

Wiring

Chamber

and

Terminals

be maintained at an “Idling” temperature. The Idle feature is also useful for preventing frost and light ice formation. When the control is in idling mode, the idling pointer ﬂashes slowly and the system relay is turned on. The heat relay is cycled on and off to maintain the slab at the “Idling” temperature.

Warm Weather Cut Off (WWCO)

If the control is in melting or idling mode and the “Slab” and “Outdoor” temperatures rise above the “Melting” temperature, the control

shuts down the melting system and enters Warm Weather Cut Off mode. During WWCO, the WWCO pointer ﬂashes slowly. The timer continues to run and normal operation is resumed when the “Outdoor” temperature drops below the “Melting” temperature.

Cold Weather Cut Off (CWCO)

Maintaining the slab at a “Melting” or “Idling” temperature in extremely cold conditions can be expensive and may even be impossible. When it does snow at these colder temperatures, the snow is usually dry, light and less slippery. The control therefore turns the melting system off when the “Outdoor” temperature drops below the “CWCO” setting. While the control is in CWCO, the CWCO pointer ﬂashes slowly. The timer continues to run until the slab temperature drops below the “Target Slab” temperature. When the outdoor temperature rises above the “CWCO” temperature, the control exits CWCO and continues with normal operation.

On Time

The control has a built in timer which is used to set the length of time the control operates the system in melting mode. The timer begins counting down when the snow melt system is turned on and the slab has reached the “Melting” temperature.

Hole for mounting screw

Meets Class B: Canadian ICES FCC Part 15 Made in Canada tektra 906-09

PRGM

Outdoor Slab Sensor Target Slab

Item

Snow Melting Control 650

Pulse Width Modulation

Melt at power up

Power

Oﬀ

C-

R+

Heat

Signal wiring must be rated at least 300V

Hole for mounting screw

Power: 24 V (ac) ± 10% 50/60 Hz 3 VA 24 V (dc) ± 10% 0.03A Relays: 240 V (ac) 10 A 1/3hp

H1113E

Time

CWCO

Idling

Melting

Start Stop

No power

Com

Slab

Sen

System

Out Sen

Date Code

Temperatures and On Time display

°C or °F indicators

Programming and Melt Start/Stop buttons

Installation

Caution

Improper installation and operation of this control could result in damage to the equipment and possibly even personal injury. It is your responsibility to ensure that this control is safely installed according to all applicable codes and standards. This electronic control is not intended for use as a primary limit control. Other controls that are intended and certiﬁed as safety limits must be placed into the control circuit.

Step One Getting ready

Check the contents of this package. If any of the contents listed are missing or damaged, please refer to the Limited Warranty and Product Return Procedure on the back of this brochure and contact your wholesaler or tekmar sales agent for assistance.

Type 650 includes: Data Brochures:

Other information available:

ote: Carefully read the Sequence of Operation section in this brochure to ensure that you have chosen the proper control and

• One Snow Melting Control 650 • One Slab Sensor 072 • One Outdoor Sensor 070

• Data Brochures D 001, D 070, D 072, D 650 • Application Brochures A 650

• Essay E 001, Essay E 005.

understand its functions within the operational requirements of your system.

Step Two Mounting

The control is mounted in accordance with the instructions in the Data Brochure D 001.

Step Three Rough-in wiring

All electrical wiring terminates in the two wiring chambers at the bottom front of the control. If the control is to be mounted on an electrical box, the wiring can be roughed-in at the electrical box prior to installation of the control (see Brochure D 001). Standard 18 AWG solid wire is recommended for all low voltage wiring to this control.

Power should not be applied to any of the wires during the rough-in wiring stage.

• Install the Outdoor Sensor 070 according to the instructions in Data Brochure D 070 and run the wiring back to the control. Do not connect the wires to the terminals yet.

• Install the Slab Sensor 072 in the slab halfway between the heating pipes or electric cables and within 1 inch of the slab surface (see adjacent diagram). The sensor should be placed approximately 3 feet (1m) from the edge of the slab. Run the wiring back to the control but do not connect the wires to the terminals yet.

• Install a 24 V (ac) Class 2 transformer with a minimum 5VA rating and run the wiring from the transformer to the control.

A Class 2 transformer must be used

. Do not

connect either of the transformer secondary wires to ground.

• Or provide a 24V DC power source and run wiring to the control location.

• Run wiring from the heating device and system circuits to the control.

1" (25mm)

Slab Sensor

SLAB

halfway between the pipes or electric cables

Step Four

Testing and connecting the wiring

Caution

These 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 — 200 Volts, and at least 0 — 2,000,000 Ohms, is essential to properly test this control. At no time should voltages in excess of 28 V be measured at any of the wires connected to the control.

Test the sensors

• This test must be performed

power is applied to the control and

before

the sensors are connected to the terminal strip.

before

Test the sensors according to the instructions printed in the enclosed Data Brochure D 072.

Test the power supply

• Ensure exposed wires are not grounded or in contact with other wires. Turn on the 24 V ac power supply and, using a voltmeter, you should measure between 20 and 28 volts between the power and common terminals.

• Turn off the power and complete the electrical connections to the terminal strip of the control.

Power and output connections

The installer should test to conﬁrm that no voltage is present at any of the wires.

• Connect the power supply to terminals

Power C — R

• Connect the heating device circuit to terminals

• Connect the system circuit to terminals

System

(1 and 2).

(3 and 4).

Heat

(5 and 6).

Sensor connections — Caution, voltage is never applied to these terminals

• Connect the Slab Sensor 072 to terminals

• Connect the Outdoor Sensor 070 to terminals

Com Sen and Slab Sen

Com Sen and Out Sen

(7 and 8).

(7 and 9).

24 V Only

1C-2R+34

Power

power supply

24 V

10A

Heat

Heat Relay

closes to turn on

heating device

System

System Relay

closes when in

melting or idling

10A

modes

Com

Sen

Do not apply

power here

Out

Slab

Sen

Slab

Sensor

Outdoor

072

Sensor

070

+ 2 hidden pages