tekmar 667 User Manual

- Data Brochure

D 667

Snow Detector & Melting Control 667

09/02

The Snow Detector & Melting Control 667 is a microprocessor-based control which operates a snow melting system. The control can operate automatically when a Snow/Ice Sensor 090 is installed or the user can manually enable and/or disable the system. The 667 controls a variable speed injection pump to provide both boiler and slab protection. When the control is not in the melting mode, the system can either be shut down or it can be maintained at an idle temperature for faster response and improved safety. The 667 control includes a large Liquid Crystal Display (LCD) in order to view system status and operating information.

Additional features include:

• Slab protection for the snow melting system

• Boiler protection

• Manual Override

• Warm Weather Shut Down (WWSD)

• Cold Weather Cut Out (CWCO)

Menu Item

Snow Detector & Melting Control 667

Variable Speed Injection

Var2Pwr

Red4Blk5Blu6Yel7Brn/

Start

Stop

Do not apply power

Boil9Com10tN211Mix12Mix13Com14Out

SlabMix Ret Sup

Melt Demand

Idle Demand

WWSD

Minimum

Maximum

Water

Melting

• Remote display and adjustment capabilities.

• Test sequence to ensure proper component operation.

• Pump exercising.

• Viscosity compensation.

• CSA C US Certified (approved to applicable UL standards)

Idle Demand

Melt Demand

Tes t

off

not testing

red

testing

red

testing paused

For maximum heat, press and hold Tes t button for 3 seconds.

Made in Canada by tekmar Control Systems Ltd.

158033

tektra 900-04

Power 115 V Relays 230 V (ac) 5 A 1/3 hp, pilot duty 240 VA Var. Pump 230 V (ac) 2.4 A 1/6 hp, fuse T2.5 A 250 V Demand 20 to 260 V (ac) 2 VA

Signal wiring must be rated at least 300 V

16 17

Melt/Idle

System Boiler

Demand Pmp 2

± 10%

18 21

19 20

50/60 Hz 600 VA

22 23 25

Melting

Sys

Power

H2029A

Output

Variable Speed

Injection Pump

Snow/Ice Sensor

090 installed with

Input

Sensor Socket

091 Optional

Input

Slab Sensor

Optional

Input

115 V (ac) Power Supply

Output

System Pump

Output

Melt Relay

Input

Universal

Sensor

Included

Remote Display Module (RDM)

Remote Start / Stop Module

Input

Universal

Sensor

Included

Input

Universal

Sensor

Included

Input

Outdoor

Sensor

Included

Input

Melt/Idle Demand

Output

System

Pump

Output

Boiler

How To Use The Data Brochure

This brochure is organized into four main sections. They are: 1) Sequence of Operation, 2) Installation, 3) Control Settings, and

4) Tro ubleshooti ng. The Sequence of Operation section has 6 sub-sections. We recommend reading Section A: General of the Sequence of Operation, as this cont ains impor tant information on the overall operation of the contro l. Then read to the sub-s ections that apply to your installation.

The Control Settings section (starting at DIP Switch Settings) of this brochure describes the various items that are adjusted and displayed by the control. The control functions of each adjustable item are described in the Sequence of Operation.

Table Of Contents

User Interface.................................................. Pg 2

Description of Display Elements ..................Pg 3

Sequence of Operation ..................................Pg 4

Section A: General Operation .............. Pg 4

Section B: Snow Melting ......................Pg 5

Section C: Boiler Operation .................Pg 7

Section D: Melting Enable / Disable .... Pg 8

Section E: Melting Operation ...............Pg 11

Section F: Idling Operation ..................Pg 12

Installation.......................................................Pg 12

Electrical Connections.......................... Pg 13

Testing The Wiring.................................Pg 15

Reference Material: Essay E 021: Mixing Methods and Sizing of Variable Speed Injection Pumps

DIP Switch Settings........................................ Pg 16

Access Levels ................................................. Pg 17

Control Settings..............................................Pg 17

View Menu .............................................. Pg 17

Adjust Menu ........................................... Pg 18

Monitor Menu .........................................Pg 20

Schedule Menu ......................................Pg 21

Miscellaneous Menu .............................Pg 22

Testing and Troubleshooting ........................Pg 23

Error Messages ..................................... Pg 24

Technical Data ................................................ Pg 28

Limited Warranty ............................................Pg 28

User Interface

The 667 uses a Liquid Cryst al Disp lay (LCD) as the method of sup plying information. You use the LCD in ord er to setup and monitor the operation of your system. The 667 has four push buttons (Menu, Item, ▲ (Start), ▼ (Stop)) for selecting and adjusting settings. As you program your control, record your settings in the Adjust Menu table which is found in the second half of this brochure.

All of the items displayed by the control are organized into various menus. These menus are listed on the left hand side of the display (Menu Field). To select a menu, use the Menu button. By pressing and releasing the Menu button, the display will advance to the next available menu. Once a menu is selected, there will be a group of items that can be viewed within the menu.

Item

The abbreviated name of the selected item will be displayed in the item field of the display. To view the next available item, press and release the Item button. Once you have reached the last available item in a menu, pressing and releasing the Item button will return the display to the first item in the selected menu.

Adjust

To make an adjustment to a setting in the control, begin by selecting the appropriate menu using the Menu button. Then select the desired item using the Item button. Finally, use the ▲ and / or ▼ button to make the adjustment.

Additional information can be gained by observing the Status field of the LCD. The status field will indicate which of the control’s outputs are currently active. Most symbols in the status field are only visible when the View Menu is selected.

Item

Menu Item

Start Stop

Display

ater

Menu Field

Displays the current menu

Status Field

Displays the current status of the control's inputs, outputs and operation

Item Field

Displays an abbreviated name of the selected item

Number Field

Displays the current value of the selected item

Melt Deman Idle Deman WW Minim

xim W Meltin

Buttons

Selects Menus, Items and adjusts settings

Symbol Description

Lock / Unlock

Displays whether the access levels are locked or unlocked.

Burner

Displays when the Boiler relay is turned on.

Pointer

Displays the control operation as indicated by the text.

°F, °C, sec, min, hr

Units of measurement.

Ovr

Mixing Device Output Scale

Shows output of injection pump. Arrows show whether the output is increasing or decreasing.

Pump

Displays when the system pumps are operating.

Override

Displays when the control is in override mode.

Warning

Displays when an error exists or when a limit has been reached.

F, °C, sec,

min, hr

Deﬁ nitions

The following defined terms and symbols are used throughout this manual to bring attention to the presence of hazards of various risk levels, or to important information concerning the life of the product.

- Warning Symbol: Indicates presence of hazards which can cause severe personal injury, death or substantial property damage if ignored.

INSTALLATION

CATEGORY II

- Double insulated

- Local level, appliances

Sequence of Operation

Section A

General

Operation

Page 4

Section B

Snow

Melting

Page 5 - 6

Section C

Boiler

Operation

Page 7 - 8

Section D

Melting Enable/

Disable

Page 8 - 10

Section E

Melting

Operation

Page 11

Section F

Idling

Operation

Page 12

Section A: General Operation

POWERING UP THE CONTROL

When the Snow Detector & Melting Control 667 is powered up, the control displays all LCD segments for 2 seconds, then the control type number in the LCD for 2 seconds. Next, the software version is displayed for 2 seconds. Finally, the control enters into the normal operating mode and the LCD defaults to displaying the current outdoor air temperature.

MIXING DEVICE

Variable Speed Injection Pump

A standard wet rotor circulator is connected to the 667 on the Var and Pwr Mix terminals (1 and 2). The 667 increases or decreases the power output to the circulator based on the system requirements. For correct sizing and piping of the variable speed injection pump, refer to Essay E 021. A visual indication of the current variable speed output is displayed in the LCD in the form of a segmented bar graph.

MIXING MAXIMUM (MIX MAX)

The MIX MAX sets the highest fluid temperature that the control is allowed to calculate as the mixing target temperature. If the control does target the MIX MAX setting, and the MIX SUP temperature is near the MIX MAX, the Maximum pointer is displayed in the LCD while the MIX SUP temperature is being viewed.

BOILER PROTECTION (Boil MIN)

The 667 is capable of providing boiler protection from cold mixing system return fluid temperatures. If the boiler sensor temperature is cooler than the Boil MIN setting while the boiler is firing, the 667 reduces the output from the mixing device. This limits the amount of cool return water to the boiler and allows the boiler temperature to recover. This feature can only be used if the Boil SENS item is set to SUP or RET. The 667 can not provide boiler protection if the Boil SENS item is set to NONE.

Mixing

Sensor

Boiler Supply

Sensor

Boiler Return

Sensor

EXERCISING (EXERCISE)

The 667 has a built-in pump and valve exercising function. The exercising period is adjustable and is factory set at 70 hours. If a pump output has not been operated at least once during every exercising period, the control turns on the output for 10 seconds. This minimizes the possibility of a pump seizing during a long period of inactivity.

Note: The exercising function does not work if power to the control or pumps is disconnected.

Section B: Snow Melting

Section B1

General

Snow Melting

Section B1: General Snow Melting

SLAB PROTECTION (∆T MAX)

The control can limit the rate at which heat is applied to the zone through the ∆T MAX setting. The ∆T (delta T) is the temperature difference between the snow melting supply temperature and the snow melting return temperature. By limiting this temperature difference, the rate at which heat is applied to the zone can be controlled and thermal stresses in the slab can be minimized. When the control is operating at the ∆T MAX, the Maximum pointer can be seen when viewing the ∆T item in the View menu. The control provides slab protection differently based on boiler sensor placement.

VISCOSITY COMPENSATION (EXCEEDING ∆T MAX)

At low temperatures, the glycol solutions used in snow melting systems become very viscous and difficult to pump. In order to overcome this condition during a cold start of a snow melting system, the 667 is allowed to exceed the ∆T MAX setting for a period of time in order to warm the glycol solution. This allows the control to compensate for the high viscosity of the glycol solution and is used when the mixing return temperature is below 30°F (-1°C). When the control exceeds the ∆T MAX setting, the Maximum pointer will flash when viewing the ∆T item in the View menu.

tensile stresses

SOFT START

When the control starts applying heat to the slab, the supply temperature to the snow melting system is ramped up over a period of time until it reaches the target mixed supply temperature. This feature helps reduce thermal stresses in the slab.

Note: This operation only occurs if the Boil SENS item is set to RET or NONE.

RUNNING TIME (RUN TIME)

The running time is the length of time that the system operates once it has reached its slab target temperature. During the time that the system is approaching its slab target temperature, the RUN TIME does not decrease. Once the system reaches its slab target temperature, the RUN TIME begins counting down. When the RUN TIME reaches 0:00 as displayed in the STATUS item in the View menu, the system has finished melting.

Note: The running time is only applicable when a manual melting enable signal starts the snow melting system. Refer to Section D1 for a description of a manual melting enable.

WARM WEATHER SHUT DOWN (WWSD)

There is a warm weather shut down for the system. When both the slab temperature of the system and the outdoor temperature exceed the system’s melting temperature by more than 2°F (1°C), the system enters into WWSD. In WWSD, the system is shut down in order to conserve energy. While the system is in WWSD, the word WWSD is displayed in the STATUS item in the View menu. The 667 turns on the WWSD pointer in the display.

COLD WEATHER CUT OFF (CWCO)

Maintaining the system at either the melting or idling temperature during extremely cold temperatures can be expensive or impossible. The control turns the snow melting system off when the outdoor air temperature drops below the Cold Weather Cut Off (CWCO) temperature. While the control is in CWCO, the word CWCO is displayed in the STATUS item in the View menu. The heater in the sensor is kept on during CWCO until the control detects moisture. If water is detected, the heater is turned off but the control retains the moisture detected information. When the outdoor temperature rises above the CWCO temperature, the control exits CWCO and if the Snow / Ice Sensor 090 detected moisture during CWCO, the control initiates melting mode. If the control has been started prior to the CWCO, it resumes the melting mode once the outdoor air temperature rises above the CWCO temperature.

STATUS (STATUS)

While in the View menu there are a number of items available to determine the current status of the system. To view the current status of the system, select the STATUS item in the View menu.

• STRT The word STRT is displayed after the snow melting system has been manually enabled. It is displayed until the

system reach es its slab tar get tempe rature. If the sys tem is at its slab target tem perat ure, STRT is di splayed for five seconds after the snow melting system has started operation. This is to verify that the control has entered into the melting mode.

• STOP The word STOP is displayed for five seconds after the snow melting system has been manually disabled. The

word STOP is also displayed if either a Remote Start / Stop Module 039, Remote Display Module 040 or the Stop button on the control stops the snow melting system and an external melt demand is still present.

• IDLE The word IDLE is displayed as long as the system is operating at its idling temperature.

• EXT The word EXT is displayed when the RUN TIME has reached 0:00 and the control still has an external melt

demand. In this situation, the system continues melting until the melt demand is removed or the control is stopped.

• DET The word DET is displayed after the snow melting system has been automatically enabled by the Snow / Ice

sensor 090 and the system is at its slab target temperature. DET is also displayed once the control is manually enabled after automatic detection by the 090 and the running time has counted down to 0:00.

• 0:00 to 23:59 hr While the system is up to temperature and melting, the remaining RUN TIME is displayed.

• INF If an infinite RUN TIME is selected and the system is melting, INF is displayed.

• WWSD When the system is in Warm Weather Shut Down, WWSD is displayed.

• CWCO When the control is in Cold Weather Cut Off, CWCO is displayed.

SNOW MELTING OVERRIDE

If the AWAY setting is selected in the Schedule menu, the snow melting system is shut down. Both the Melting and Idling temperatures are ignored as long as the control remains in the AWAY mode.

SYSTEM PUMP OPERATION (Sys P1 and System Pmp 2)

The system pump contacts close and remain closed as long as the system is either in the Melting or Idling mode. The system pump contacts shut off if the control is in CWCO, WWSD, or if there is no call for Melting or Idling.

MELTING CONTACT OPERATION

The Melting contact (terminals 21 and 22) closes and remains closed as long as the system is in melting mode. This contact can be used as an external signal to indicate that the system is currently in melting mode. This contact can also be used as a means of prioritizing or enabling multiple snow melting controls.

PURGE

The system pumps continue to operate for up to 2 minutes after the last demand is removed. This purges the residual heat from the boiler into the snow melting slab. If the boiler temperature drops below the Boil MIN setting after 20 seconds, the purge is aborted and the system pumps are turned off.

Section C: Boiler Operation

Section C1

Boiler Supply

Sensor

Section C2

Boiler Return

Sensor

Section C3

No Boiler

Sensor

Section C1: Boiler Supply Sensor

BOILER SENSOR ON THE SUPPLY (Boil SENS = SUP)

When operating a boiler that is dedic ated to a snow melting system, the 667 is designed to operate the boiler as efficiently as possible. The boiler is cycled based on the mixing supply fluid temperature. This is to provide longer and more efficient boiler cycles. This mode of operation only works if the Boil SENS item is set to SUP.

BOILER MINIMUM (Boil MIN)

The Boil MIN is the lowest water temperature that the control is allowed to use as a boiler target temperature. If the boiler is operating, and the boiler supply temperature is near the Boil MIN setting, the Minimum pointer turns on in the LCD while the Boil SUP temperature is being viewed. If the installed boiler is designed for condensing or low temperature operation, set the Boil MIN adjustment to OFF.

FIRE DELAY (FIRE DLY)

The FIRE DLY is the delay time that may occur between the time that the 667 closes the Boiler contact and when the b urn er f ires. Thi s de lay is usually the result of burner pre-purge or other forms of time delay built into the burner’s safety circuits.

Boiler Contact Closes

Fire

Delay

Boiler Temperature

Boiler Fires

Minimum On Time

Minimum Off Time

Time

Fire

Delay

Minimum

On Time

BOILER MASS (Boil MASS)

The Boil MASS setting allows the 667 to adjust to different types of heat sources depending on their thermal mass.

Light (LITE)

The LITE setting is selected if the boiler that is used has a low thermal mass. This means that the boiler has a very small water content and has very little metal in the heat exchanger. A boiler that has a low thermal mass comes up to temperature quite rapidly when fired. This is typical of many copper fin-tube boilers.

Medium (MED)

The MED setting is selected if the boiler that is used has a medium thermal mass. This means that the boiler either has a large water content and a low metal content or a low water content and a high metal content. This is typical of many modern residential cast iron boilers or steel tube boilers.

Heavy (HEVY)

The HEVY setting is selected if the boiler that is used has a high thermal mass. This means that the boiler has both a large water content and a large metal content. A boiler that has a high thermal mass is relatively slow in coming up to temperature. This is typical of many commercial cast iron and steel tube boilers.

DIFFERENTIAL (DIFF)

An on / off heat source such as a boiler must be operated with a differential in order to prevent short cycling. With the 667, either a fixed or an automatic differential may be selected.

Fixed Differential

The differential is centered around the target temperature. If the temperature drops 1/2 the differential below the target temperature, the 667 closes the boiler contact to fire the boiler. If the temperature rises 1/2 of the differential above the target temperature, the 667 opens the boiler contact to turn off the boiler.

Auto Differential (AUTO)

If the AUTO differential is selected, the 667 automatically adjusts the differential setting under the current load conditions to avoid short cycling.

Section C2: Boiler Return Sensor

BOILER SENSOR ON THE RETURN (Boil SENS = RET)

The boiler sensor should be located on the boiler return if the 667 is one of many controls that can call for boiler operation. When in the return mode, the 667 provides a boiler enable through the Boiler contact. The 667 no longer tries to control the boiler supply water temperature directly, but allows the boiler to operate at its operating aquastat setting when required. If this mode of operation is selected, the boiler pump should either operate continuously, or be operated in parallel with the system pump contact (Sys P1). When the mixing device begins to ramp up, the Boiler contact closes on the 667. The Boiler contact remains closed until the mixing device no longer requires heat. With the sensor on the boiler return, the 667 is still capable of providing boiler protection as described in section A.

Section C3: No Boiler Sensor

Off

Differential

Time

Snowmelt Load

NO BOILER SENSOR (Boil SENS = NONE)

The 667 is capable of operating without a boiler sensor if desired. Without a boiler sensor, the 667 is unable to provide boiler protection. In this mode of operation, the Boiler contact is used to provide a boiler enable. When the mixing device begins to ramp up, the Boiler contact on the 667 closes. The Boiler contact remains closed until the mixing device no longer requires heat. This type of application is typical if the 667 is drawing heat from a source that already incorporates some form of boiler protection.

Section D: Melting Enable / Disable

Section D1

Snow Melting

Enable

Section D2

Snow Melting

Disable

Section D1: Snow Melting Enable

The snow melting system can be enabled manually or automatically. A melting enable signal applied to the control places the system into the melting mode. If a melting enable signal is applied once the system is already in the melting mode, the control responds to the last command received.

MANUAL MELTING ENABLE

A manual melting enable signal requires the user to manually start the snow melting system and can be provided from the Start button on the control, Remote Start / Stop Module 039, Remote Display Module 040, or an external melt demand.

Start Button on the Control

The snow melting system is enabled by pressing the Start button on the control while in the View menu. The control then displays the RUN TIME setting to allow the user to adjust it. Once the snow melting system is enabled, the word STRT is displayed for at least 5 seconds in the STATUS item while in the View menu. If the Start button on the control is pressed while the system is already melting and up to temperature, the running time counter is reset to the RUN TIME setting.

Remote Start / Stop Module 039

The snow melting system is enabled by pressing the button on the front of the 039. Whil e the zone is coming up to temperature, a green indi cator light flash es on the front of the 039. Once the zone is up to temperature and the RUN TIME is counting down, the green indicator light on the front of the 039 is on solid.

Remote Display Module 040

The snow melting system is enabled by pressing the ▲ button on the 040 while in the View menu. The 040 then displays the RUN TIME setting to allow the user to adjust it. Once the snow melting system is enabled, the word STRT is displayed for at least 5 seconds in the STATUS item while in the View menu.

Menu Item

Start / Stop

Start Stop

External Melt Demand (DIP switch set to Melt Demand)

The snow melting system is enabled when a voltage between 24 and 240 V (ac) is applied across the Melt/Idle Demand terminals (15 and 16). An external melt demand must be present for at least 4 seconds in order to start the snow melting system. If the RUN TIME reaches 0:00 and the external melt demand is still present, the control continues melting until the external melt demand is removed or the system is otherwise stopped.

24 to 240 V (ac)

Note: This operation only occurs if the Idle Demand / Melt Demand DIP switch is set to the Melt Demand position.

AUTOMATIC MELTING ENABLE (Snow / Ice Sensor 090)

The 667 can use the Snow / Ice Sensor 090 to provide an automatic melting enable signal to start the snow melting system. The control continually monitors the 090 for the presence of moisture. Once moisture is detected, the Water pointer is displayed in the LCD and the snow melting system is enabled.

Water Detection Sensitivity (SENSTVTY)

The 667 has a sensitivity setting which compensates for varying outdoor conditions which could affect how the moisture detector in the 090 interprets the presence of moisture. This adjustable setting is available through the SENSTVTY item in the Adjust menu of the control. As snow becomes contaminated with dirt, and as the sensor its elf becomes dir t y, the control may incorrectly ind icate the pres ence of water. If this condition occurs, clean the surface of the sensor and / or turn down the SENSTVTY set ting. If the snow in your area is very clean, the SENSTVTY setting may need to be increased before snow is detected. If AUTO is selected, the control automatically adjusts the sensitivity level used to detect moisture.

Idle Demand

Melt Demand

StopStart

Melt / Idle Demand

+ 19 hidden pages