Tekmar D 650 User manual

Snow Melting
Control 650
Pulse Width Modulation
On
Time
PRGM
FC
Item
Date
S/N
Power supply:
24V 60Hz 3VA
Relay capacities:
120V 10A 1/3hp
5
System
Melt at power up
On
Off
6
34
Heat
No Power
789
Com
Sen
Slab
Sen
Out
Sen
24 V Only
21
CR
Power
Outdoor
Slab Sensor
Target Slab
Start Stop
CWCO
Idling
Melting
Warm Weather Cut Off (WWCO)
Ifthecontrolisinmeltingoridlingmodeandthe“Slab”and“Outdoor”temperaturesriseabovethe“Melting”temperature,thecontrol
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.
Whentheoutdoortemperaturerisesabovethe“CWCO“temperature,thecontrolexitsCWCOandcontinueswithnormaloperation.
On Time
Thecontrolhasabuiltintimerwhichisusedtosetthelengthoftimethecontroloperatesthesysteminmeltingmode.Thetimerbegins
counting down when the snow melt system is turned on and the slab has reached the “Melting” temperature.
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
TheSnowMeltingControl650isamanualcontrol;inorderto
start the melting system with the control powered up, the
“Start”button ispushed.Themeltsystemcanalso bestarted
by setting the “Melt at power up” DIP switch to “On” and
poweringupthecontrol.Whenthecontrolisinmeltingmode,
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
moreinformationonPWM,seeEssay000.Oncetheslabhas
reachedthe“Melting”temperature,atimerstarts.Thecontrol
remains in melting mode until the timer “On Time” reaches
zero, the “Stop” button is pushed, or the remote switch is
turned off.
Note:Iftheremoteswitchisturned offandonagaintorestart
the system, the switch must be kept off for at least 1
second for the control to fully power down.
Idling Mode
Whenthesnowmeltingsystemstartsfromacoldtemperature,
the time required for the slab to reach “Melting” temperature
canbeexcessive. To decrease this start up time, the slabcan
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.
- Data Brochure
Snow Melting Control 650 06/94
D 650
Sequence of Operation
°C or °F
indicators
Programming
mode
indicator
Item
identifiers
Wiring
Chamber
and
Terminals
Programming
and Melt
Start/Stop
buttons
Item
selection
and display
button
Hole for mounting screw
Hole for mounting screw
Temperatures
and On Time
display
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
manuallybya button onthecontrolor by anoptionalremoteswitch. Built in energysavingfeaturesinclude 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
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.
F
Snow Melting
Control 650
Pulse Width Modulation
On
Time
Item
Outdoor
Slab Sensor
Target Slab
Start Stop
CWCO
Idling
Melting

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 ac, 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 ac be
measured at any of the wires connected to the control.
Test the sensors
• This test must be performed before power is applied to the control and before the sensors are connected to the terminal strip.
Test the sensors according to the instructions printed in the enclosed Data Brochure D 001.
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 an AC
voltmeter, you should measure between 20 and 28 volts at the secondary side of the transformer.
• 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 (1 and 2).
• Connect the heating device circuit to terminals Heat (3 and 4).
• Connect the system circuit to terminals System (5 and 6).
Sensor connections — Caution, voltage is never applied to these terminals
• Connect the Slab Sensor 072 to terminals Com Sen and Slab Sen (7 and 8).
• Connect the Outdoor Sensor 070 to terminals Com Sen and Out Sen (7 and 9).
2
Caution
Improper installation and operation of this control could result in damage to the equipment and possibly even
personalinjury. Itisyourresponsibilitytoensurethatthiscontrolissafelyinstalledaccordingtoallapplicablecodes
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
Checkthe contents of this package. If any of the contents listed are missing or damaged, please refer to the Limited Warranty
andProductReturnProcedureonthebackofthisbrochureandcontactyourwholesalerortekmarsalesagentforassistance.
Type 650 includes: •One Snow Melting Control 650 • One Slab Sensor 072 • One Outdoor Sensor 070
• One Data Brochure D 650 • One Data Brochure D 001 • Application Brochures A 650
Other information available: • Essay E 000, Essay E 600
N ote: Carefully read the Sequence of Operation section in this brochure to ensure that you have chosen the proper control and
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.
Installation
• InstalltheOutdoorSensor070accordingtotheinstructionsinDataBrochureD001andrunthewiringbacktothecontrol.
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
shouldbeplaced approximately 3feet(1m)from the edgeoftheslab. Run thewiring
back to the control but do not connect the wires to the terminals yet.
• Install a 24 V ac Class II transformer with a minimum 5VA rating and run the wiring
from the transformer to the control.
A Class II transformer must be used . Do not
connect either of the transformer secondary wires to ground.
• Run wiring from the heating device and system circuits to the control.
1" (25mm)
halfway between the
pipes or electric cables
Slab Sensor
SLAB
Power should not be applied to any of the wires during the rough-in wiring stage.
24 V Only
Do not apply
power here
24 V ac
power
supply
Heat Relay
closes to turn on
heating device
System Relay
closes when in
melting or idling
modes
1
C
2
R
34
10A 10A
Heat System
56Slab
Sen Out
Sen
89
Slab
Sensor
072 Outdoor
Sensor
070
Power
7
Com
Sen

Step Five Troubleshooting
First observe the system operating parameters. The source of the problem can often be identified by noting a temperature or time
readingwhichseemsunreasonable. Observing what the control is doing, and understanding the sequence of operationgreatlyaids
in troubleshooting. If there is a sensor fault, the control displays an error message. Use the error message table provided below to
determine which circuit has the fault and then refer to Step Four for testing of the wiring and sensors.
3
Settings
Outdoor temperature - the temperature measured by the Outdoor Sensor.
Slab Sensor temperature - the temperature measured by the Slab Sensor. This sensor should be 1” below the slab surface.
Target Slab temperature - the control calculates a “Target Slab” temperature to maintain the slab surface at the “Melting” or “Idling”
setting when the Slab Sensor is placed 1” below the slab surface and halfway between the pipes or electric cables (See Step Three
of this brochure). The “Target Slab” temperature is calculated from the “Melting” or “Idling” setting and the measured “Outdoor”
temperature. Asthe“Outdoor”temperaturedropsorthe“Melting”or“Idling”settingisraised,the“TargetSlab”temperatureincreases.
On Time - when the control is in melting mode, the On Time display indicates the time left until the control exits melting mode. When
programming, the On Time can be set from 30 minutes to 19 hours 50 minutes or it can be set to “Inf” (Infinite). When the On Time
is set to “Inf”, the control remains in melting mode indefinitely until the “STOP” button is pressed.
Melting temperature - the “Melting” temperature is the desired slab surface temperature when the control is in melting mode and is
also used as the Warm Weather Cut Off temperature. The slab “Melting” temperature is usually set based on the local weather
conditions. In some areas, heavy snowfall can load a slab at temperatures well above freezing; in these areas, the “Melting”
temperature is set higher. In general if the melting system response is sluggish, increasing the “Melting” temperature causes the
system to melt faster. It is important to remember that increasing this setting increases the snow melt system energy consumption.
Idling temperature -the“Idling”temperatureissetbased on the requirements of the user. To minimize the timerequiredfortheslab
to reach “Melting” temperature, “Idling” is set slightly below freezing (<32°F). To prevent black ice or frost formation, “Idling” is set
slightly above freezing (>32°F). It is important to remember that idling increases energy consumption. Idling can also be set to “Off”.
ColdWeatherCutOff(CWCO)-the“CWCO”temperatureisthelowestoutdoortemperatureatwhichthemeltsystemoperates. This
setting is based on the economics of melting in extreme conditions and the melting capabilities of the snow melt system.
On
Time
Outdoor
Slab Sensor
Target Slab
CWCO
Idling
Melting
Outdoor Sensor Open/Short Circuit
The display flashes “Err” and the
“Outdoor” pointer. The control con-
tinues operation assuming an out-
door temperature of 20°F (-7°C).
On
Time
Outdoor
Slab Sensor
Target Slab
CWCO
Idling
Melting
Slab Sensor Open/Short Circuit
The display flashes “Err” and the
“Slab Sensor” pointer. The control
shuts down the melting system with
this error.
Press and Release the
“Item” button to change the
display from the “Outdoor”
temperature to the “Slab
Sensor” temperature.
Use the arrow keys to program
the “Melting” temperature.
Note: The control automatically exits out of programming when the buttons are left alone for 20 secondsNote: The control automatically exits out of programming when the buttons are left alone for 20 seconds
When the control is
powered-up, all display
elements are turned on.
POWER ON
After approximately three
seconds, the “Outdoor”
temperature is displayed.
VIEWING
Press and Release the
"Item" button to change the
display to the "Target Slab"
temperature.
Press and Release the
"Item" button to change the
display to the "On Time"
remaining.
PROGRAMMING
When no Idling function is
desired, set Idling to “OFF”.
Use the arrow keys to program
the “Idling” temperature.
Use the arrow keys to set
the “CWCO” temperature.
When no CWCO is desired,
set CWCO to “OFF”.
Use the arrow keys to switch
between “°F” and “°C”.
Use the arrow keys to program the
“On Time" in hours and minutes.
If the control is not in
melting or idling mode, no
"Target Slab" temperature is
displayed.
If the control is not in
melting mode no “On
Time” is displayed.
Continue to
Press and
Release
the “Item” button.
The word “PRGM” is
displayed and the “On
Time” pointer flashes.
On
Time
F
Outdoor
Slab Sensor
Target Slab
CWCO
Idling
Melting
Press and Release the
“Item” button to change the
display to the “Melting”
temperature.
Press and Release the
“Item” button to change
the display to the “Idling”
temperature.
Press and Release the
“Item” button to change the
display to “°F” or “°C”.
On
Time
Outdoor
Slab Sensor
Target Slab Melting
PRGM
CWCO
Idling
On
Time
F
Outdoor
Slab Sensor CWCO Idling
Target Slab Melting
On
Time
Outdoor
Slab Sensor CWCO Idling
Target Slab Melting
On
Time
PRGM
F
Outdoor
Slab Sensor
Target Slab
CWCO
Idling
Melting
On
Time
F
Outdoor
Target Slab
CWCO
Idling
Slab Sensor Melting
PRGM
On
Time
F
Outdoor
Target Slab
CWCO
Slab Sensor Melting
Idling
PRGM
On
Time
F
Outdoor
Target Slab Idling
Slab Sensor Melting
PRGM
If the DIP
switch is set to
“Melt at power
up”, the control
switches into
“Melting” mode
when it is
powered up.
If the control is
already powered up
and you are not
programming,
Press and Release
the "Start" button.
When the control is in
melting mode the
melting pointer
flashes.
INITIATING
OPERATING MODE
When the control is not in CWCO or WWCO, the
melt system is turned on as follows:
OR
On
Time
F
Outdoor
Slab Sensor
Target Slab
CWCO
Idling
Melting
On
Time
F
Outdoor
Target Slab
CWCO
Idling
Slab Sensor Melting
Press and Release the
“Item” button to change the
display to the “CWCO”
temperature.
On
Time
Outdoor
Slab Sensor
Target Slab Melting
PRGM
CWCO
Idling
On
Time
F
Outdoor
Target Slab
CWCO
Idling
Slab Sensor Melting
PRGM
CWCO
Melt at power up
On
Off
Item
Start Stop
On
Time
Outdoor
Slab Sensor CWCO Idling
Target Slab Melting
On
Time
F
Slab Sensor
Target Slab
CWCO
Idling
Melting
Outdoor
On
Time
PRGM
FC
Outdoor
Slab Sensor
Target Slab
CWCO
Idling
Melting
Item
Start Stop
Item
Start Stop
Item
Start Stop
Item
Start Stop
Item
Start Stop
Item
Start Stop
Item
Start Stop
Item
Start Stop
Item
Start Stop
Item
Start Stop
Item
Start Stop
Item
Start Stop
Item
Start Stop

Step Six Before you leave
• Install the wiring cover over the wiring chamber and secure it to the base with the screw provided. Place the front cover over the
control and snap it into place.
• Placethisbrochure,andallotherbrochuresrelatingtotheinstallation,intheprotectiveplasticbagsuppliedwiththecontrol. Place
the bag in a conspicuous location near the control for future reference.
• It is important to explain the operation of the control and melting system to all users who may be operating it.
Technical Data
Theinstallermustensurethatthiscontrolanditswiringareisolatedand/orshieldedfromstrongsourcesofelectromagneticnoise.Conversely,
thiscontroldoesnotexceedtheClassBlimitsforradionoiseemissionsfromdigitalapparatusassetoutintheRadioInterferenceRegulations
of the Canadian Department of Communications. If this equipment does cause interference, the user is encouraged to try and correct the
interference by reorienting the receiving antenna and/or relocating the receiver with respect to this equipment.
Le présent numérique n’émete pas de bruits radioeléctriques dépassant les limites applicables aux appareils numériques de Classe B
prescrites dans le réglement sur le brouillace radioeléctrique édicté par le Ministére des Communications du Canada.
Limited Warranty and Product Return Procedure
Limited Warranty: tekmar warrants to the original purchaser each tekmar
product against defects in workmanship and materials when the product is
installed and used in compliance with tekmar's instructions. This limited
warranty covers the cost of parts and labour provided by tekmar to correct
defects in materials and/or workmanship. Returned products that are fully
operational are not considered a warranty case. tekmar also does not cover
parts or labour to remove, transport or reinstall a defective product. tekmar will
not be liable for any damage other than repair or replacement of the defective
part or parts and such repair or replacement shall be deemed to be the sole
remedy from tekmar. This warranty shall not apply to any defects caused or
repairsrequired asa result ofunreasonable ornegligentuse, neglect,accident,
improper installation, or unauthorized repair or alterations. In case of defect,
malfunction or failure to conform to warranty, tekmar will, for a warranty period
of24monthsfromthedateofinvoicetotheoriginalpurchaseror12monthsfrom
the date of installation of the product, whichever occurs first, repair, exchange
or give credit for the defective product. Any express or implied warranty which
the purchaser may have, including merchantability and fitness for a particular
purpose, shall not extend beyond 24 months from the date of invoice or 12
months from the date of installation of the product, whichever occurs first.
Replacements: tekmar can send replacement products if requested. All
replacements are invoiced. Any possible credit for the replacement will only be
issued once the replaced product has been returned to tekmar.
Product Return Procedure: Productsthat are believed to have failed must be
returnedtotekmarControlSystemsLtd.4611-23rdStreet,VernonB.C.Canada
V1T 4K7 when agreed to by tekmar. The installer or other qualified service
person must, at the owner's expense, determine which component has failed. The
product must be returned complete with all of its components (sensors, base, etc.).
Products must be returned together with the proof of purchase to the original
purchaser who then returns the product to tekmar after receiving a Return Goods
Authorization (RGA) number from tekmar.
Please include the following information with the product. The full address of the
original purchaser, the RGA number and a description of the problem.
From the U.S.A., in order to avoid customs charges, products must be returned via
USPostwiththepackageclearlymarkedwiththeRGAnumber,producttypeandthe
statement "Canadian Product returned for repair". For shipping purposes the
product can be valued at one half list price.
1) If returned during the warranty period and the product is defective, tekmar will
issue full credit for the returned product less cost of missing parts.
2) Ifreturnedduringthewarrantyperiodandtheproductisfullyoperational,tekmar
will return the product to the original purchaser for a testing cost of $30.00 plus
postage.
3) Ifreturnedduringthewarrantyperiodandtheproductisnotdamagedandisfully
operational, tekmar can take back the product for a return charge of 40% of the
product's net value. This request has to be specified otherwise the product will
be returned with a testing cost of $30.00 plus postage.
4) If returned after the warranty period and the product needs repair, tekmar will
repair and return the product. Repair and postage costs will be invoiced.
tekmar's repair costs are calculated at $30.00 / hour plus the cost of parts. If
the repair costs will be more than $60.00 a repair estimate will be sent to the
original purchaser.
4
All specifications are subject to change without notice.
Printed in Canada on recycled paper.
Product designs, software and literature are Copyright © 1994 by:
tekmar Control Systems Ltd. and tekmar Control Systems, Inc.
In North America: tekmar Control Systems Ltd., Canada
tekmar Control Systems, Inc., U.S.A.
Head office: 4611 - 23rd Street
Vernon, B.C. Canada V1T 4K7
Tel. [phone] Fax. [phone]
Snow Melting Control 650
Literature — D 650, A650, D 001, E 000, E 600
Control — Microprocessor PI control; This is not a safety (limit) control.
Packaged weight — 1.3 lb. (600 g), Enclosure C, PVC plastic
Dimensions — 4-3/4” H x 2-7/8” W x 7/8” D (120 x 74 x 22 mm)
Approvals — Meets DOC regulations for EMI/RFI.
Ambient conditions — Indoor use only, -20 to 120°F (-30 to 50°C), < 90% RH non-
condensing.
Power supply — Class 2, 24 V ac ±10% 50/60 Hz 3 VA
Relays — 120 V ac 10 A1/3 hp, pilot duty 240 VA 2 A
Sensors — NTC thermistor, 10 kΩ@ 25°C ±0.2°C ß=3892
included: Outdoor Sensor 070 and Slab Sensor 072.
Control accuracy — ±0.5°F (±0.25°C) with up to 1000 feet (300m) of 18AWG wire
to sensors.
On Time — 0:30 to 19:50 hours to ‘Infinite’
Melting — 34 to 45°F (1 to 7°C)
Idling — Off, 23 to 34°F (-5 to 1°C)
CWCO — Off, -22 to 23°F (-30 to -5°C)
Snow Melting
Control 650
Pulse Width Modulation
On
Time
PRGM
FC
Item
Date
S/N
Power Supply:
24V 60Hz 3VA
Relay Capacities:
120V 10A 1/3hp
5
System
Melt at power up
On
Off
6
34
Heat
No Power
789
Com
Sen
Slab
Sen
Out
Sen
24 V Only
21
CR
Power
Outdoor
Slab Sensor
Target Slab
Start Stop
CWCO
Idling
Melting
H11131