(4,7mm).187 DIA (4) CONTROLLER SUPPLY VOLTAGE : 115 volts _+ 10%, 50/60 Hz., 4 V.A. maximum 230 volts + 100, 50/60 Hz., also available.

Transcription

1 DATA SHEET MODEL O (4,7mm).187 (4,7mm).187 DIA (4) SPECIFICATIONS : CONTROLLER SUPPLY VOLTAGE : 115 volts _+ 10%, 50/60 Hz., 4 V.A. maximum 230 volts + 100, 50/60 Hz., also available. CONTROLLER OUTPUT : Isolated zero cross-over solid state switch rated at 10 amps maximum, 0.5 amps minimum. HEATER SUPPLY VOLTAGE : This will vary depending upon application. Power bridge must be designed, for the application. The supply voltage for the heater an be the same as is used for the controller. Hcwever, the heater can be operated fr3m a separate source from 24 to 230 volts A.C., 50/60 Hz. HEATER TEMPERATURE RESISTANCE CHARACTERISTICS : The proper heater material and selection depends upon the application. Consult factory ' for information. Page 1 of 13 11IUAYNCO INC. W'NONA. MINNESOTA FAST EIGHTH STREET PHONE

2 DATA SHEET-~,.=-I-')"~='-."-- MODEL. 4t- SPECIFICATIONS : SET POINT RANGE : Set point is adjustable by a remote connected potentiometer. The range of adjustments are selected for the application. Heaters are available for operation up to 2000 F. CYCLE TIME : The sampling rate is adjustable over a range of 1 to 5 seconds minimum. OPERATING AMBEINT TEMPERATURE : 50 F to 125 F. LED INDICATOR : A red LED indicator lamp on the terminal board indicates the operational status of the controller. The LED is on when the controller is applying power to the heater. EXTERNAL WIRING DIAGRAM : ~TFOS 1(I1(1 10,11 IFS101(0 I S CYCLE 1(11(1 il0( 01 Temperature Set Pot I l. C I[Ii(1 11s,1.C rxlilfl~ -SOKII-1 L : t, ID L2 Heater 115 VAC, 50/60 Hz. 24 to 230 VAC Page 2 of 13 WAYNCO INC. WINONA, MINNESOTA EAST EIGHTH STREET PHONE

3 DATA SHEET ;)_- ;-_-,-' MODEL -azzz=9 APPLICATION OF HEAT-SENSE CONTROL r~~~ -~ ~t Y-OJ ;J ; The Model heat-sense temperature controller utilizes the principle of change in resistance of the heater with temperature to provide the feedback signal to the controller to maintain a constant temperature of the heater. In other words, the resistance heater supplies the thermal requirements of the system as well as the feedback signal for control. The response time is essentially instantaneous since the heater cannot change temperature without a corresponding change in resistance. In a conventional temperature control system the feedback signal is obtained by means of a separate sensor such as a thermocouple, thermistor, RTD, etc. Normally, the heater used in a conventional system maintains a relatively constant resistance over a wide range of temperatures. The response time in a conventional system depends upon the thermal time constant between the heater and sensor. Both systems have obvious advantages. The choice depends upon the control application. In some applications superior results can be obtained by a combination of both systems. There are other types available to suit various applications. This bulletin covers only one type of heat-sense controller. The key to successful application of the heat-sense technique is to satisfy the thermal requirements of the system before choosing a particular heat-sense control or designing the power bridge. A temperature control system utilizing the heat-sense principle consists of a resistance heater, power bridge, electronic controller package and solid state power relay or switch. Since the heater'supplies the thermal requirements as well as the feedback signal, a power bridge is required. Fig. 1 illustrates the basic heat-sense power bridge. Fig. 1 The heater and shunt resistor form one arm of the bridge and the set pot and associated resistors form the opposite arm of the bridge. The voltage (el) Page 3 of 13 &4 WIN ONA MINNESOTA EAST EIGHTH STREET PHONE

4

5 D~`;TA SHEET M03EL TEMP2RATURE CONTROLLER BRIDGE BOARD ASS'Y. The following is a list of discrete ccmpcnents needed to make up this Bridge Board Assembly. Use as listed or equivalent. RESISTORS : Qty : 1 ea. R1, R2, R5, R6 Waynco P/N : %, 1/2W Manufacturer : IRC (TO-60) Standard 1% resistance values available. r1.sminj -+jo(r.15d1a MAX 00 SCHEMATIC SYMBOL TRIM POTS : Qty : l. ea. R3, R4 Waynco P/N : turn Manufacturer : Bourns (3006P) Standard resistance values needed : lk, 2K, 5K, 10K, 20K ohm i 2s F+--.76MAX+{ ~~4.06 ~- LEADS WILL FIT A.04 DIA HOLE.20 2 WIPER CLOCKWISE SHUNT RESISTOR : Qty. 1 ea. Waynco P/N : %, 5W Manufacturer : Dale (LVR-5) Resistance values needed :.025,.05,.10,.25,.50 ohms r 2.00 r W ~F SCHEMATIC SYMBOL.04 DIA W1NONA, MINNESOTA SCHEMATIC SYMBOL 1265 EAST EIGHTH STREET Page 5 of 13 PHONE

6 DATA SHEET MODEL -2 ~ TERMINALS FOR SHUNT RESISTOR : Qty. 2 ea. -~ P/N : o0 Manufacturer : VACO (11208) DIA FOR NO.8 SCREW ~-~ ~-.14 D1A --r~ ~--DIA FOR NO.18 THRU 22 GA.WIRE REMOTE SET POT : Qty. 1 ea. 77Lo W P/N : ,3,c) Manufacturer : Clarostat (Series 43 H.T.) Standard resistance values : 25, 100, 200, 250, 500, 1K ohms SCHEMATIC SYMBOL WINONA, MINNESOTA Page 6 of EAST EIGHTH STREET PHONE

7 D E N T I A L PROCEDURE FOR POWER BRIDGE DATA SHEET MODEL l. The value of the following parameters must be determined prior to design of the bridge circuit. a) Line Voltage, E L b) Resistance of the heater at room temperature, 72 F c) Resistance of the heater at the low end of the temperature range, R HL d) Resistance of the heater at the high end of the temperature range, RHH 2. The maximum value of the shunt resistor RS MAX. i s now calculated. Its value should be the maximum allowable by the following two constraints : a) The maximum power dissipation rating of the shunt resistor, PS MAX. b) The maximum input voltage of the temperature control, 0.6 volts. < PS MAX. < 0.6 VOLTS I 72 F = EL RS MAX. and RS MAX., where 72 F)2 72 F 72 F The value of the shunt resistor is now selected. 3. The current through the heater at the low (IHL) and high (IHH) end of the temperature range is now calculated. 4. The voltage across the shunt resistor at the low (E SL ) and high (E SH ) end of the temperature range can now b~ calculated. ESL I HL RS, E SH I HH RS The change in the voltage across the shunt resistor, is needed to determine the value of the set pot. h ES = ESL ESH 5. The total power dissipated by the resistors in the bridge circuit should be limited to approximately 0.6 watts to avoid changes in the resistance due to the temperature coefficient of the resistors. Therefore for operation on 120V line, the bridge current should be approximately amps and on 240V line :005 amps. The currents for other line voltages can be calculated from the equation : I = 1.2 NOTE! Power Dissipation = RMS (Power), since bridge circuit is EL 2 half wave. Page 7 of 13 WINONA, MINNESOTA EAST EIGHTH STREET PHONE

8 C O N F I D E N T I A L DATA SHEET 1 -=> = -=~~' " ~'= J MODEL 6. The approximate value of the set pot can now be calculated from : Rp = 10 AES The closest standard value pot is chosen, Rp S. The current through the pot, IRP, is calculated using the selected standard pot value with the equation : IRP = 10 AES RpS 7. To provide for calibration of the set pot at the low end of the temperature range, R4 and R5 are connected in parallel with the set pot. These resistors provide +20% calibration adjustment. The value of R5 is determined by : R5 = 10 A ES.2 IRP R4 is selected to have a minimum value 20 times RPS. 8. The value of R6 is now determined from the equation : R6 = 10 ESN IRP +.2 (IRp) 9. The total resistance of the bridge circuit is determined next. RTOTAL = EL IRp `.2 I RP) From RTOTAL, the values of Rl, R2 and R3 can be calculated. Rl + R2 + R3 = RTOTAL - RD-R6 For + 20,o adjustment a- the high temperature end of the temperature range, R3 should be made.4 (RTOTAL - Rp - R6) and Rl + R2 = RTOTAL - Rp - R6 - R3 Rl and R2 are made equal in value to divide the power dissipation. Therefore, Rl = RTOTAL - rp - R6 - R3 2 = R2 2 The calculation of the bridge resistors is now complete. WAYNCO INC. Page 8 of 13 WINONA MINNESOTA EAST EIGHTH STREET PHONE

9 C O N F I D E N T I A L DATA SHEET ! 7_O::) :, MODEL DESIGN EXAMPLE 1. a), Line Voltage, EL = 240VAC b) 72 F = 20 ohms = 27 ohms d) RHH = 55 ohms F = 240VAC = 12 amperes 20 ohms PS MAX. = 5 watts RS MAX. < 5 watts 12 amps 2 <.034 ohms RS MAX. < 0.6 volts 12.amps <.050 ohms A shunt resistor of.025 ohms, 5 watts is selected. 3. IHL = 240 volts IHH = 240 volts 27 ohms = 8.88 amps 55 ohms 4.36 amps 4. ESL = (8.88 amp) (.025 ohms) _.222 volts ESH = (4.36 amps) (.025 ohms) _.109 volts A ES =.222 volts volts =.113 volts 5. 1 = 1.2 = 1.2 =.005 amps EL Rp = (10 ) (.113) = 226 ohms.005 The closest standard value pot is 250 ohms. IRP = (10) (.113) = amps R4 = (10) (.113) = 1250 ohms R5 = (20) (250) = 5K ohms -C.2( ) 8. R6 = (10) (.109) ohms (.00452) + (.2) (.00452) Page 9 of 13 ea4, WINONA MINNESOTA EAST EIGHTH STREET PHONE

10 C 0 N F I D E N T I A L DATA SHEET MODEL 9. RTOT = 240 = 44,247 ohms ( R3 = 44, = 43,797 R3 = (.4) (43,797) = 17,519 closest pot value is 25K ohms. Rl + R2 = 43,797-25,000 = 31,297 2 Rl = 31,297 = 15,648 = R2 2 R1, R2 = 15.4K ohms. (B Page 10 of 13 WINONA MINNESOTA EAST EIGHTH STREET PHONE

11 DATA SHEET MODEL SYSTEM CALIBRATION PROCEDURE system may be calibrated by utilizing a temperature sensor such as a thermistor, thermocouple, etc. attached to the heater surface in combination with a suitable temperature indicator. Following is the recommended procedure : 1. Make all connections to the temperature control system. CAUTION : Check all connections for mechanical and electrical integrity. Never energize the system with the shunt disconnected as the controller may be permanently damaged. 2. Turn the temperature set pot, low temperature adjust and high temperature adjust to their minimum temperature settings counter clockwise). Turn the cycle time adjust to its maximum counter clockwise direction. Supply power to the controller only. 3. With the heater supply voltage disconnected and the cycle time pot maximum counter clockwise, the LED should remain off. Slowly turn the cycle time pot in a clockwise direction until the LED turns on. The LED should remain on. Connect the heater supply voltage. The LED will begin to cycle on-off when the heater reaches temperature. This will be the minimum temperature at which the heater can be operated. 4. Turn the temperature set pot to its maximum temperature setting. 5. Adjust the high temperature pot to obtain the desired maximum temperature of the surface to be controlled as indicated by the temperature monitor. 6. Turn the temperature set pot to its minimum temperature setting. 7. Adjust the low temperature pot to obtain the desired minimum temperature of the surface to be controlled as indicated by the temperature monitor. 8. Repeat steps 4 through 7. Re-adjust the high and low temperature pots if necessary. 9. Turn the set pot to the desired operating temperature. 10. Decrease the cycle time if the temperature is fluctuating to obtain minimum change in temperature. NOTE : Decreasing the cycle time will increase the minimum obtainable temperature. C5 Page 11 of 13 WINONA MINNESOTA EAST EIGHTH STREET PHONE

12 DATA SHEET 22o J- ^,- MODEL TROUBLE ANALYSIS AND SERVICE CHART SYMPTOM CAUSE REMEDY Over Heats Shorted Solid State Connect jumper wire across Switch shunt resistor. If power turns off, switch okay. If not, replace control. Over Heats Controller Indicator If solid state switch from Light OFF above test okay, replace controller. Over Heats Controller Indicator Check inter-connecting Light ON. wire to terminals. If connections per connection diagram and system continues to over heat, replace controller. Power On Heater Heater Open Replace Heater. Also But Not Heat check wiring and all connections. Pulses ON-OFF Improper Calibration Repeat Calibration But Temp. Below Procedure. Set Point Pulses ON-OFF High Resistance Check heater resistance But Temp. Below connection in heater and all connections. Set Point circuit. Pulses ON-OFF Bridge Board not Tighten all screws on But Temp. Below screwed down Bridge Board Set Point - tightly. Pulses ON-OFF Set Pot. leads Pl Check wiring of remote Temp. Below Set and P3 reversed. Set Pot. Point Page 12 of 13 WINONA, MINNESOTA EAST EIGHTH STREET PHONE

13 DATA SHEET MODEL-&2=_ b TROUBLE ANALYSIS AND SERVICE CHART SYMPTOM CAUSE REMEDY Pulse ON-OFF Temp. Be'l ow Set Point. Bad Controller Replace Controller. Unit does not pulse Heater Power. Indicator light on, controller is off. Improper adjustment, cycle rate adj. Turn Clockwise until indicator light comes on. If unable to attain this condition, replace controller. Unit does not pulse Heater Power and Indicator Light On. Improper wiring. Indicates broken lead or open circuit in Heater Supply or Heater. Check wiring. If wiring okay, replace controller. Of WINONA MINNESOTA EAST EIGHTH STREET Page 13 of 13 PHONE