Honeywell S7080A Multizone Control System Instruction Manual

Honeywell S7080A Multizone Control System

Specifications

• Manufacturer: [Manufacturer Name]
• Model: [Product Model]
• Dimensions: [Product Dimensions]
• Weight: [Product Weight]
• Power Source: [Power Source Type]
• Battery Life: [Battery Life]
• Color: [Product Color]
• Material: [Product Material]

INSTRUCTIONS

THIS SOLID-STATE SYSTEM IS A COMPONENT-FOR-COMPONENT FIELD REPLACEMENT FOR THE RANCO EAS LODAPT SYSTEM. THE BASIC SYSTEM CONTROLS UP TO 12 ZONE DAMPERS, 3 HEATING STAGES, 3 COOLING STAGES, AN INTEGRATED ECONOMIZER,  AND MODULATING VALVES FOR HOT WATER AND CHILLED WATER. OPTIONAL UNITS PROVIDE CONTROL OF UP TO 12 ADDITIONAL ZONES, 5 STAGES OF ELECTRIC HEAT, VARIABLE AIR VOLUME (VAV) SYSTEM FAN, AND A 4TH STAGE OF COOLING. ALTHOUGH  THE FEATURES AND RANCO CROSS-REFERENCES FOR ALL COMPONENTS IN THE W7080 MULTIZONE SYSTEM ARE LISTED, ONLY THE SIX COMPONENTS ILLUSTRATED ON THIS COVER PAGE ARE COVERED IN DETAIL IN THIS SPECIFICATION SHEET. THE  REMAINING COMPONENTS ARE COVERED IN SEPARATE SPECIFICATION SHEETS.

1. W7080A Load Analyzer (Ranco EA3) provides spdt relay switching of 3 stages of heating and 3 stages of cooling and provides modulating output to economizer and valve motors in response to the highest heating and cooling demand from zone thermostats. The analyzer is the source of 24 Vdc power for zone thermostats and sensors.
2. The modulated DC voltage signal from the zone thermostat, modified by the zone discharge sensor, provides direct control of the associated zone damper.
3. Pilot duty spdt relays control heating and cooling stages. IJ Economizer uses an M745K or M745L motor to provide the true first stage of cooling, using outdoor air whenever possible.
4. The system switches all stages off when power is interrupted, and switches stages on when power is restored. Compressor turn-on time delays must be incorporated for each compressor.
5. Quick-connect, 1/4 in. male terminals for reliable, convenient connections.
6. Power supplies in the W7080A Load Analyzer and the W7084A Zone Adder are short-circuit protected. Short circuits of 24 Vdc from the load analyzer or zone adder will not damage their power supplies.
7. The system is an Underwriters Laboratories component recognized and meets the guidelines of ASHRAE 90-75 and the U.S. Department of Defense.
8. Night setback and cooling shutdown for individual or all zones by addition of a time clock.

SPECIFICATIONS

IMPORTANT

• THE SPECIFICATIONS GIVEN IN THIS PUBLICATION DO NOT INCLUDE NORMAL MANUFACTURING TOLERANCES, THEREFORE, THIS UNIT MAY NOT MATCH THE LISTED SPECIFICATIONS EXACTLY. ALSO, THIS PRODUCT IS TESTED AND CALIBRATED UNDER CLOSELY CONTROLLED CONDITIONS, AND SOME MINOR DIFFERENCES IN PERFORMANCE CAN BE EXPECTED IF THOSE CONDITIONS ARE CHANGED.

MODELS: Ranco components are cross-referenced to Honeywell components in Table 1.
TABLE 1 – RANCO-HONEYWELL COMPONENT CROSS-REFERENCE

SYSTEM COMPONENTS: All components of the W7080 Multizone System are briefly described in this section. For detailed information on 7046B and C7100B Sensors, T7080A, B Thermostats, and W7081A Limit Controller, refer to the associated
specification sheets (form number in parentheses): C7046B (60-2350), C7100B (60-2539), T7080A,B (60-2527), W7081A (60-2512). C7046B Temperature Sensor (Ranco TR1-1001) is the non-averaging type with 6 in. [152 mm] probe for

ORDERING INFORMATION

WHEN PURCHASING REPLACEMENT AND MODERNIZATION PRODUCTS FROM YOUR TRADELINE
WHOLESALER OR YOUR DISTRIBUTOR, REFER TO THE TRADELINE CATALOG OR PRICE SHEETS FOR
COMPLETE ORDERING NUMBER, OR SPECIFY~

1. Order number.
2. Order additional system components and system accessories separately.

FROU HAS SIONS, USE I A FUNERAL INFORMATION, OR WOULD LIKE TO COMMENT ON OUR

1. YOUR LOCAL HONEYWELL RESIDENTIAL SALES OFFICE (CHECK WHITE PAGES OF YOUR PHONE DIRECTORY).
2. RESIDENTIAL GROUP CUSTOMER SERVICE HONEYWELL INC., 1885 DOUGLAS DRIVE NORTH MINNEAPOLIS, MINNESOTA 55422 (612)542-7500 IN SANTE NATIONA SALES AND SERVICE OFFICES ALE MINI PAL IT ES OF THE WORLD ONTARIO use in ducts where space does not permit the longer C7100B.
   • C7100B Averaging Temperature Sensor (Ranco
   • TR1-1002,-1003) installed in a hot deck, cold deck, and mixed-air duct to provide limit signals for limit controller operation. Also installed in the charge air duct of each zone to provide anticipation for the T7080 Thermostat. The sensor probe length is 13 in. [330 mm).
   • H205A Enthalpy Controller (Ranco J15) senses the heat content (temperature and humidity) of outdoor air. Allows the use of outdoor air for free cooling.
   • S7080A Simulator (Ranco TE1) portable unit pro- vides check of the system by substituting adjustable do voltage for zone thermostat and sensor signals.
   • T7080A, B Solid State, dual set point Thermostat (Ranco TR3, TR4) modulates zone dampers and supplies load demand signal to load analyzer.
   • Single voltage ramp design has variable, 3 F-30 F (1.7 C-16.7 C) deadband. For complete
   • T7080A, B information, refer to Form No. 60-2527.
   • T7080A has a built-in sensor, and T7080B requires a remote sensor. 195325B 4th Stage Cooling Board (Ranco
   • EA5-C9100) optional unit permits the addition of a 4th stage of cooling to the system.
   • ELECTRICAL RATINGS:
   • Voltage and Frequency-24 Vac, 50/60 Hz.
   • Maximum Power Consumption-W7080A, 10 VA;
   • W7081A, 0.29 VA; W7082A, 1.5 VA; W7083A, 1.4
   • VA; W7084A, 3 VA.
   • Codable Ratings (spat pilot duty relays) -See

TABLE 2 – RELAY CONTACT RATING FOF
W7N80A W7083A 195325R

NOTE: VA ratings are not valid when the maximum load is connected to both NORMALLY OPEN and NORMALLY CLOSED contacts.

INPUT SIGNALS: See Table 3.TARLE 3 _ SYSTEM INPUT SIGNALS

THERMOSTAT DEADBAND: 3 F to 30 F [1.7 C TO 16.7 CJ, depending on separation between heat and cool set point levers on T7080A.
STAGE DIFFERENTIALS: See Fig. 1.

FIG. 1-W7080A STAGE OPERATING POINTS, DIFFERENTIALS, AND THROTTLING RANGES.

• COLD DECK LOW LIMIT: Limits cold deck temperature to selectable set points of 45 F, 50 F, or 55 F 17.2 C, 10 C, or 12.8 C].
• HOT DECK HIGH LIMIT: Limits hot deck temperature to selectable set points of 90 F, 110 F, or 130 F [32.2 C, 43.3 C, or 54.4 CJ.
• ECONOMIZER MIXED AIR LIMIT: The Economizer motor modulates the outdoor air damper to a minimum position when the mixed air temperature is below the set point of the W7081A Limit Controller. This set point is selectable to 50 F, 55 F, or 60 F [10 C, 12.8 C, or 15.6 C], with a 10 F [5.6 C] fixed throttling range.
• INTEGRATOR MINIMUM OUTPUT: Selectable from 0 to minus 8 Vdc (0 to 80 percent fan motor speed).
• ZONE DISCHARGE SENSOR AUTHORITY: 20:1 which means a 20 F [11.1 C] rise at the zone discharge sensor produces a voltage change equal to a 1 F [0.5 C] rise at the space thermostat.
• AMBIENT TEMPERATURE RISE:
• Operating- Minus 40 F to plus 150 F [minus 40 C to plus 65 C].
• Shipping — Minus 30 F to plus 150 F [minus 34 C to plus 65 C].
• MOUNTING: The W7080A, W7081A, W7082A, W7083A, and W7084A units each attach with 4 screws through mounting holes in the base (screws not provided).
  The 195325B 4th Stage Cooling Board can be mounted on a flat surface using the bracket provided. See individual specification sheets for mounting details.

DIMENSIONS

FIG. 2- MOUNTING DIMENSIONS FOR W7080A, W7081A, W7082A, W7083A, W7084A UNITS IN IN. [mm IN BRACKETS].

• UNDERWRITERS LABORATORIES INC. COMPONENT
• RECOGNIZED: File No. SA481, Guide No. SDFY2D (applies to W7080A, W7083A, and 195235B units only.
• ADDITIONAL SYSTEM COMPONENTS: C7100B (13 in.) Averaging
• Temperature Sensor-one sensor in the hot deck, one sensor in the cold deck, and one sensor in mixed air to supply the 3 sensor input signals required by the W7081A
• Limit Controller. Also, one sensor is installed in each zone discharge duct to supply anticipation to the T7080A Zone Thermostat.

NOTE : Economizer mixed air sensor (C7100B or C7046B) may be mounted in the cold deck if it is desired to close the economizer when mechanical cooling is operating. May be used as a remote return air sensor when used with the T7080B Zone Thermostat.
Where space is insufficient for the 13 in. [304.8 mmJ probe of the C7100B, the C7046B single-point temperature sensor, with 6 in. [152.4 mm] probe, may be installed. 195325B 4TH STAGE COOLING BOARD- controls the operation of the two- stage compressor in the system.
Mounts separately from other components on bracket supplied.

H205A ENTHALPY CONTROLLER-Controls econo- mizer operation in response to enthalpy (total heat content) of outdoor air. Signals economizer to close outdoor air damper (or modulate to minimum position) when enthalpy is above H205 set point, and to open damper on a call for cooling when enthalpy is below-set point.

NONSPRING RETURN MOTORS-M734J, M744D have a solid state balance relay and operate on 24 Vac, 50/60 Hz.

• M734J produces 35 Ib.-in. [4 N.m] torque over 160 degree stroke. Modulates zone discharge damper in response to 10.5 to 13.5 Vdc signal from zone thermostat.
• M744D produces 150 lb.-in. [17 N.m] torque with 90 or 160-degree non-adjustable stroke. Modulates hot water or chilled water valves in response to 4-7 Vdc signal from W7081A Limit Controller. Requires separate power supply.

SPRING RETURN MOTORS— 745K, L, P motors have solid-state balance relays, and require separate 24 Vac, 50/60 Hz power supplies.

• M745K or M745L motor operates economizer damper in response to the modulating signal of 14-17 Vdc signal from W7081A.
• M745P modulates hot water or chilled water valves in response to 4-7 Vdc signal from
  W7081A. Requires 4074EAC Resistor Kit (orderseparately).

TIME DELAY RELAYS- To  improve the stability of the system and minimize energy use, 5-minute turn-on time delays should be added to all heat- ing and cooling loads. These relays should be wired between cooling and heating stage switching outputs of the W7080A Load Analyzer W7083A Electric Heat Sequencer and 195325B 4th Stage Cooling Board) and the heating and cooling equipment.

SYSTEM ACCESSORIES: Transformers

• AT20-20 VA
• AT72-40 VA
• ATOO. 7E VA

IMPORTANT: The transformer used to power the W7080A Load An analyzer can also be used to power stage relays in the W7083A Electric Heat Sequencer (if used).The M744 and M745 motors each require a separate transformer to ensure electrical isolation. NEVER GROUND THE SECONDARY OF ANY TRANSFORMER USED TO POWER ANY SYS- TEM COMPONENT.

• Q209A MINIMUM POSITION POTEN
• TIOMETER-mounts directly on M734, M744,
• M745 motors; controls the minimum open position of the damper.
• Q605 DAMPER LINKAGE-connects motor to damper; includes a motor crank arm.
• Q618 VALVE LINKAGE-connects Modutrol motor to modulate hot or chilled water valves.
• S963A REMOTE MINIMUM POSITION POTENTOMETER provides remote manual control of the minimum open position of the economizer motor.
• MODULATING WATER VALVES-use appropriate valve with Super Modutrol motor and Q618 Linkage to provide proportional control of hot or chilled water flow.

COMPRESSOR AMBIENT LOCKOUT
THERMOSTAT with direct expansion cooling system to prevent compressor operation when the outdoor air temperature falls below the economizer set point.

• T675A Temperature Controller.
• L6018C Temperature Controller.

ECONOMIZER CHANGEOVER CONTROLLER -holds economizer at minimum position whenever outdoor air temperature or enthalpy is above controller set point.

• H205A1038 or H205A 1046 Enthalpy Controller.
• 675A Temperature Controller.
• L6081C Temperature Controller.

NIGHT SETBACK -provides a heating setback of 6 F to 22 F [3.3 C to 12.2 C]. Requires connection of a 1 percent resistor and S6005 Time Clock contact
connected between terminals 1 and 5 of T7080A or T7080B Thermostat.

• 802139BAAC Resistor (10.0 K 8) provides 6 F
  [3.3 C] setback.

• 802139EJHB Resistor (4.87 K ®) provides 10 F
  [5.6 C] setback.

• 802139CGHB Resistor (2.67 KS) provides 14 F
  [7.8 C] setback.

• 802139BEDB Resistor (1.43 K S) provides 18 F
  [10 C] setback.

• 802139GJBA Resistor (681 ohms) provides 22
  F [12.2 C] setback.

MORNING WARMUP THERMOSTAT- holds outdoor air damper fully closed following night set-back and until return air temperature exceeds the selected set point.

• T675A Temperature Controller.

• L6018C Temperature Controller.

• T675A Temperature Controller.
  S43 SAIL SWITCH-activates circuits when minimum airflow is maintained in the duct. Deactivates circuit below minimum airflow.

• 191444B METAL COVER-designed to protect the W7080A, W7081A, W7082A, W7083A, and W7084A components when mounted on an open surface. Overall dimensions of units with metal cover in place: 6-5/8 in. long, 4-5/16 in. wide, 4-13/16 in. high [168.3 x 109.5 x 122.2 mm].

INSTALLATION

WHEN INSTALLING THIS PRODUCT

1. Read these instructions carefully. Failure to follow them could damage the product or cause a hazardous condition.
2. Check the ratings given in the instructions and on the product to make sure the product is suitable for your application.
3. The installer must be a trained, experienced service technician.
4. After installation is complete, check out product operation as provided in these instructions.

CAUTION

1. Disconnect the power supply before connecting the wiring to prevent electrical shock and equip- ment damage.

IMPORTANT
Each M744 and M745 motor must have its transformer for isolation. The transformer used to power the W7080A can also be used to power load relays only, providing the VA rating of the transformer is not exceeded. NEVER GROUND THE SECONDARY OF ANY TRANSFORMER USED TO POWER ANY SYSTEM COMPONENT.

LOCATION AND MOUNTING

• The W7080A, W7082A, W7083A, and W7084A units can be located on any flat wall or control panel where they are not exposed to the weather and do not exceed ambient temperature ratings: These units are each mounted with 4 screws through the mounting holes in the base.
• The 195325B 4th Stage Cooling Board, if used, should be located near the W7080A and mounted on the bracket supplied.
• If the optional metal cover (Part No. 191444B) is used, allow at least 4-3/4 in. [120.7 mm] clearance above the W7080 units to allow removal of the cover for checkout or service.
• Mount other system components according to in-installation instructions supplied with the individual units.

WIRING: Disconnect the power supply before connecting the wiring to avoid electrical shock or equipment damage. All wiring must comply with local codes and ordinances. When replacing Ranco units with the Honeywell equivalent units, care should be taken to insure proper replacement wiring. The equivalent Ranco and Honey-Well terminals have identical designations except in the W7080A, W7081A, and T7080 units. A cross reference of terminal designations for these 3 units is given in Table 5.

TABLE 5 – DIFFERENCES IN HONEYWELL TO RANCO TERMINAL DESIGNATIONS FOR W70804 W7081A AND T7080

Connections to Honeywell components in a multizone system are shown in Fig. 3A.
The wiring of the multizone system with night setback is shown in Fig. 3B.

BLOWER MOTOR SPEED-VAV SYSTEM
An adjustment, located on the side of the W7082A case, provides for setting minimum blower motor speed. In the fully clockwise position, this potentiometer gives 0 V (0 percent speed). In the fully counterclockwise position, the minimum output voltage is minus 8 V (80 percent speed). To set the minimum speed, disconnect all zone inputs and connect a dc voltmeter with a 0 to 10 V range to the Ref and Load terminals. Connect positive meter lead to Ref terminal, negative meter lead to Load terminal. Adjust the control until the voltmeter reads the desired voltage for min- imum speed.

WARNING

• POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PRO.
• TECTION AS REQUIRED. DO NOT GROUND ANY TRANSFORMER SECONDARY IN THE SYSTEM.
• NOT AVAILABLE FROM HONEYWELL.
• REMOTE SENSOR USED WITH T7080B ONLY.
• C7100B OR C7046B REMOTE RETURN AIR SENSOR MAY BE SUBSTITUTED C70468 SINGLE POINT TEMPERATURE SENSOR MAY BE SUBSTITUTED IF SHORTER PROBE LENGTH IS NECESSARY (SEE FORM 60-2539).
• THE W7080A LOAD ANALYZER, M744, AND M745 MOTORS REQUIRE SEPARATE TRANSFORMERS. M734 MOTORS DO NOT REQUIRE SEPARATE TRANSFORMERS.
• FOR WIRING CONVENIENCE, TERMINALS 3, 7, AND 8 ARE ALL EQUIVALENT COMMON TERMINALS.

3A-WIRING OF HONEYWELL COMPONENTS IN A MULTIZONE SYSTEM WITH UP TO 12 ZONES, 3 STAGES OF HEAT, AND AN ECONOMIZER.

• SETBACK RESISTORS SHOULD BE 1/8 W, 1%, METAL FILM TYPE. (10.0K FOR 6 F: 4.87K FOR 10 F: 2.67K FOR 14 F: 1.43K for 18 F: 681 OHMS FOR 22 F).
• LOW POWER SWITCHING RELAY CONTACTS, SUCH AS R4222N REQUIRED TO SWITCH NIGHT SETBACK RESISTOR. A LOW VOLTAGE COIL RELAY (R8222N) MAY BE USED WITH 24 Vac TRANSFORMER IF DESIRED.

OPERATION

T7080A,B THERMOSTAT

• A solid-state thermostat (T7080A or T7080B) is mounted in each zone of a multizone system to provide zone temperature control. The thermostat provides a signal voltage that modulates the zone damper motor and also provides zone demand input to the W7080A Load Analyzer.
• On a call for cooling (zone temperature rise), the zone thermostat output voltage rises at the rate of 5 V per degree F (9 V per degree C) from 12 V to a high of 22 Vdc.
• On a call for heating (zone temperature fall), the thermostat output voltage drops 5 V per degree F (9 V per degree C) from 12 V to a low of 2 Vdc. Within the deadband between the heating and cooling set points, the thermostat output voltage is constant at 12 Vdc. Anticipation in the zone is provided by a C7100B or C7046B sensor installed in the zone discharge duct and connected to the zone thermostat.

W7080A LOAD ANALYZER
The analyzer selects only the highest and lowest voltage signals from the zone thermostats (highest signal from zone of greatest cooling demand, lowest signal from zone of greatest heating demand). These two voltage signals are sent to the W7081A Limit Controller where they are modified in response to inputs from the C7100B or C7046B Sensors in the hot and cold decks. The modified signals are returned to the analyzer as HT (heating) and C (cooling) inputs that control the heating and cooling stages. The voltages at which the heating and cooling stages are switched on and off are shown in Table 6. The analyzer operates from a 24 Vac source and provides 24 Vdc to the zone thermostats, W7081A and W7083A units.

ECONOMIZER
Economizer operation is initiated on a call for cool- ing when the high signal voltage (12 to 22 Vdc) from the W7080A passes through the W7081A and H205 En- enthalpy Controller to the economizer motor. The econo- mizer motor will begin to open the damper when the

TABLE 6 – LOAD ANALYZER STAGE SWITCHING VOLTAGES

Cooling demand signal reaches 14 V, provided the mixed air temperature is above the W7081A set point, and the H205 contacts are closed. When the demand signal reaches 17 V, this damper will be fully open. If the economizer does not satisfy the cooling demand, the signal will continue to rise until mechanical cooling comes on at 18.5 V.

ZONE DISCHARGE DUCT SENSOR
A C7100B or C7046B Sensor is installed in each zone discharge duct to anticipate changes in zone temperature based on discharge air temperature to eliminate droop and overshooting. The sensor has an authority of 20:1, meaning that a 20-degree change in temperature at the sensor causes the same output voltage change as a 1-degree change at the zone thermostat.

DAMPER MOTOR
A 24 Vac damper motor is installed in each zone and linked to the damper(s) in the zone discharge air duct to control air delivered to the zone from both the hot and cold decks. The motor control circuit operates over a range of 10.5 to 13.5 Vdc, supplied by the zone thermostat. At 10.5 V (call for maximum heating), the motor fully opens to the hot deck and fully closes to the cold deck, providing maximum zone heating. At 12 V (zone temperature at the set point), the motor opens damper(s) to the midpoint (or to the minimum position). At 13.5 V (call for maximum cooling), the motor fully opens to the cold deck and fully closes to the hot deck for maximum cooling.

W7081A LIMIT CONTROLLER
The W7081A Limit Controller limits the maximum or minimum temperatures of the hot and cold decks and of the mixed air by supplying modified demand signals to the W7080A Analyzer and to the economizer. The the controller contains 3 printed circuit boards designated Economizer/Mixed Air Low Limit A5, Cold Deck Low Limit A6, and Hot Deck High Limit A7. These boards have jumper-selectable set points for temperature limits, using sensors in the decks for temperature input signals.

ECONOMIZER LIMIT
The input to the economizer board is the HI zone demand voltage from the W7080A Analyzer. This board modifies the signal based on a deviation of mixed air temperature from the limit set point. This modified signal will decrease from 17 V down to 14 V over a 10 F [5.6 C] throttling range as mixed air temperature drops. The set point is at the midpoint of the throttling range (15.5 V). Mixed air set point selections on the W7081A Limit Controller are 50 F, 55 F, and 60 F [10 C, 13 C, and 16 C] (Fig. 4)-

FIG. 4-ECONOMIZER/MIXED AIR LOW LIM- IT-MAXIMUM VOLTAGE OUTPUT.

NOTE: To prevent the economizer operation from introducing cool air to the hot deck when there is a call for heating, an economizer lockout relay may be installed. The relay coil is wired in parallel with the first stage of heating with the normally closed contacts controlling the output from terminal 1 of the W7081A Economizer/Mixed Air Low Limit A5.

COLD DECK LIMIT
The input to the cold deck board is also the HI signal voltage from the load analyzer. This limit adjusts the voltage downward as the cold deck temperature (measured by the cold deck sensor) approaches the limit set point. The voltage decreases by 0.6 V per degree F drop in cold deck temperature (1 V per degree C). At the cold deck limit set point, the voltage will be limited to 13.5 V (the turn-off point of the first stage of cooling). Cold deck limit set point selections on the W7081A are 45 F, 50 F, and 55 F [7 C, 10 C, and 13 C] (Fig. 3B). The cold deck output signal is fed to input terminal C of the W7080A to control cold deck cooling stages.

FIG. 5-COLD DECK LOW LIMIT-MAXIMUM VOLTAGE OUTPUT.

HOT DECK LIMIT
The input to the hot deck board is the LO signal from the load analyzer. This limit adjusts the voltage upward as the hot deck temperature (measured by the hot deck sensor) approaches the limit set point. The voltage increases 0.4 V per degree F [0.7 V per degree C] as the hot deck temperature increases. At the hot deck limit set point, the voltage is 6 V minimum (first stage heat on). Hot deck limit selections are 90 F, 110 F, and 130 F [32 C, 43 C, and 54 C]. The hot deck output signal is fed to the HT input terminal on the W7080A to control hot deck heating stages (Fig. 6).

NOTE: If the cold deck limit is not used, jump the HI terminal to the C terminal on the W7080A. If the hot deck high limit is not used, jump the LO terminal to the HT terminal on the W7080A. If the mixed air limit is not used, connect the economizer motor (through the H205 Enthalpy Controller) to the HI terminal on the W7080A.

FIG. 6-HOT DECK LIMIT- MINIMUM VOLTAGE OUTPUT.

MODULATING HEAT AND COOL OUTPUTS
A motorized valve with a 4 to 7 Vdc motor control input may be used in the W7080 system to provide modulated heating and cooling.

MODULATED HEATING
For modulated heating, the motor is connected to the (—) 24 VDC terminal and HT terminal on the W7080A. This arrangement provides hot deck limit action. If hot deck limit action is not desired, the motor is connected to the LO terminal rather than the HT terminal on the W7080A. The motor and valve must be fully open at 4 Vdc and fully closed at 7 Vdc.

MODULATED COOLING
For modulated cooling, the motor is connected to the (+) 24 VDC terminal and the C terminal on the W7080A. This provides cold deck limit action. If cold deck limit action is not desired, the motor is connected to the HI terminal rather than the C terminal on the W7080A. The motor is controlled by the difference in the voltage between C (+12 to +22 Vdc) and the +24 Vdc supply. The difference decreases on a call for cooling from 12 V down to 2 V. The motor and valve
must be fully open at 4 V and fully closed at 7 V.

4TH STAGE COOLING
A 4th stage of cooling that turns on at 18 V and off at 16.5 V may be added to the system where two-speed compressors are used. The 4th stage of cooling cycles before the first stage to ensure the start of the two-speed compressor at high speed. If space demand does not require a high-speed compressor, the 4th Stage Cooling Board will cycle off to allow low-speed operation. The input for the 4th Stage Cooling Board is from the C terminal of the W7080A if cold deck limit action is desired, or to the HI terminal if no limit action is desired.

W7082A LOAD INTEGRATOR
The load integrator provides an output signal that can be used to control the volume of air delivered to the zones of a multizone VAV (variable air volume) system. Control is in response to the average heating or cooling demands of up to 12 zones. When average zone de- mand decreases, fan speed will also decrease, min- imizing drafts and conserving energy. Up to 12 zone thermostats-each with a range of 2-22 Vdc-can be connected to the W7082A. The authority of any zone can be increased by connecting the thermostat in that zone to two or more integrator inputs. Unused inputs automatically assume a 12 V level (no demand for heating or cooling). Solid state circuits in the W7082A integrate all zone inputs and produce an output voltage of 0 to minus 10 Vdc that is directly proportional to average deviation from the set point voltage of 12 V (Fig. 7). The W7082A output voltage provides the input for an inverter type blower motor speed control (not available from Honeywell). At 0 V, the blower motor will stop. At minus 10 V, the motor will run at full speed. A field adjustment is provided on the W7082A to set the minimum output voltage (minimum blower speed). This voltage is adjustable from 0 to minus 8 Vdc (0 to 80 percent of full blower speed) and is factory-set at minus

FIG. 7-PERFORMANCE CHARACTERISTICS OF W7082A INTEGRATOR.
4.5 Vdc (45 percent of full blower speed). Blower speed should never be reduced below the level required for minimum building ventilation requirements. The W7082A operates from a 24 Vac power source.

W7083A ELECTRIC HEAT SEQUENCER

• The W7083A Electric Heat Sequencer provides se- sequential switching of 5 stages of electric heat in response to heating demand in the zones of a multizone system. The sequencer operates on 24 Vdc, obtained from the W7080A Load Analyzer. The W7083A is used in lieu of the 3 heating stages of the W7080A when electric heat is used.
• When power to the sequencer is interrupted, all heat stages are turned off. When power is restored, stages are restored in sequence H1, H2, H3, H4, H5. A period of approximately 60 seconds is required to sequence all stages on.
• When the signal input to the sequencer is interrupted, stages are turned off in the sequence H2, H1, H3, H4, and H5. A period of approximately 15 seconds is required to sequence all stages off. Input to the sequencer is the limited LO signal output from the W7081A Limit Controller. This signal is de- terminated by zone demand, modified by the temperature in the hot deck, and based on the set point selected in the W7081A Limit Controller. Voltages at which heat relays are switched on and off are shown in Table 7. The relationship of switching of the 5 heat stages is shown in Fig. 8.

TABLE 7 – HEAT STAGE RELAY SWITCHING VOLTAGES

FIG. 8W7083A ELECTRIC HEAT SEQUENCER STAGE ON-OFF AND OVERLAP.

W7084A ZONE ADDER

• The W7084A Zone Adder is used in multizone systems with more than 12 zones. The adder monitors the 2 to 22 Vdc signals from zones 13 through 24 and supplies the highest and lowest of these signals to the W7080A Load Analyzer.
• The W7084A operates from a 24 Vac power source and supplies regulated 24 Vdc for up to 12 zone thermostats.

195325B 4TH STAGE COOLING BOARD
The 4th Stage Cooling Board operates from the limited HI signal produced in the W7081A Limit Controller. The 4th stage of cooling is energized at 18 V and is turned off at 16.5 V. This 4th stage overlaps some other cooling stages (Fig. 1).

CHECKOUT

After completing the installation, verify system operation by performing the Multizone System Checkout below. If a fault is discovered, use the Component Checkout that follows to locate the faulty components). For terminal locations, see Fig. 3A or 3B.
MULTIZONE SYSTEM CHECKOUT DC POWER CHECK

1. With 24 VAC connected to the 24 VAC terminals of the W7080A, W7082A and (if present) the W7084A, check for 24 Vdc at the 24 VDC terminals on the W7080A, W7081A, W7082A, W7083A, and (it present) the W7084A.

THERMOSTAT OUTPUT

1. Check for 24 Vdc between terminals 2 (+) and 8 (-) on each T7080 Zone Thermostat.

2. On each T7080, measure the do output voltage between terminal 4 (output) and 3 (COM). Check that the same voltages are also present between the -24 VDC terminal and the corresponding zone input terminals on the W7080A (and on the W7084A Zone Adder if installed).
   SYSTEM CONTROL VOLTAGES

3. On the W7081A Limit Controller, check that the voltage between terminal 7 and terminal 1 (on mixed air cold deck limit) is 12 V or greater.
   NOTE: If these voltages are not within these limits, the fault is either in the A5, A6 limit boards or in the wiring between W7080A and W7081A.

4. Check that the voltage between terminal 7 and terminal 1 (A7 hot deck limit only) is less than 12 V and greater than the voltage between terminals 2 and 7.
   NOTE: If voltage is not within these limits, the fault is either in the A7 limit board or in the wiring between W7080A and W7081A.

5. If the W7084A Zone Adder is installed, check that the voltage between HI and (—) terminals is the same on both W7080A and W7084A (about 0.6 V lower than the highest zone input voltage to the W7080A).

6. Also, check that the voltage between LO and (-) terminals is the same on both W7080A and W7084A (about 0.6 V higher than the lowest zone input voltage to the W7080A.

COMPONENT CHECKOUT

COMPONENT CHECKOUT

W7080A LOAD ANALYZER

W7081A LIMIT CONTROLLER

COMPONENT CHECKOUT

W7081A COLD DECK LIMIT (A6)

W7081A HOT DECK LIMIT (A7)

W7082A INTEGRATING ANALYZER

W7082A INTEGRATING ANALYZER

W7084A ADDER

195325A 4TH STAGE COOLING BOARD

Dear Customer,

• Please send your comments and suggestions to:
• Honeywell Inc.
• We welcome your comments and suggestions for improving this publi10400 Yellow Circle Drive cation. Your assistance is greatly appreciated and will enable us to provide
• Minnetonka, Minnesota 55343 better technical information for you.
• ATTN: Publications Supervisor MN38-3247
• HONEYWELL MINNEAPOLIS, MN 55408 INTERNATIONAL Sales Offices in all principal cities of the world. Manufacturing in Australia, Canada, Finland, France, Germany, Japan, Mexico, Netherlands, Spain, Taiwan, United Kingdom, U.S. A.
  PRINTED IN U.S.A.

FAQ

Frequently Asked Questions

• Q: What is the warranty period for the [Product Model]?
  • A: The warranty period for the [Product Model] is [Warranty Period].
• Q: How do I contact customer support for assistance?
  • A: For any inquiries or assistance, please contact our customer support team at [Customer Support Phone Number] or email us at [Customer Support Email].
• Q: Can I use the [Product Model] with other devices?
  • A: Yes, the [Product Model] is compatible with a wide range of devices, including [Device Compatibility].
• Q: How long does the battery last on a single charge?
  • A: The battery life of the [Product Model] is approximately [Battery Life].

References

• Manual-Hub.com – Free PDF manuals!

Read User Manual Online (PDF format)

Read User Manual Online (PDF format)  >>

Download This Manual (PDF format)

Download this manual  >>