1 Instruction Manual for the 110 VAC Draw-off Controller System Introduction This Electronic Draw-off Controller is specifically designed for use in the Maple syrup industry. It has several features designed to refine the Maple sap evaporation process, allowing the user to maximize Maple syrup grade. Key features include: Digital temperature/set point display The DOC-1000 series controllers feature a high resolution digital temperature display, allowing continuous monitoring of sap temperature in tenths of a degree F increments. The temperature display has been adjusted to accurately read temperature changes of 0.1 degrees near the nominal draw-off point (219 degrees F) and is accurate to within 0.5 degrees. Further absolute temperature accuracy is not required for the evaporation process, because the boiling temperature is affected by other variables, such as barometric pressure. The draw-off temperature should always be determined by measuring syrup density (specific gravity). Adjustable set point Once the proper syrup density is obtained, the user can easily and quickly establish the draw-off temperature by adjusting the set point to the displayed temperature. This is done by holding the set point adjust lever up or down to increase or decrease the set point. Alarm functions The DOC-1000 series controllers can detect various system failures. An alarm will sound if any of the following conditions occur: (a) If the sap temperature rises 1.0 degree above the temperature at which the valve turned on (normally the set point temperature), (b) if the temperature probe is disconnected or shorted, (c) if the valve is disconnected or fails, or (c) if a digital controller failure is detected. This self-test capability can detect some common failures, but is not intended to replace the watchful eye of the user. The DOC should never be operated unattended, since failures can occur which the DOC cannot detect. If the DOC detects a failure, the Troubleshooting section of this manual should be referred to before attempting any corrective action. Hazards The DOC-1000 was designed to minimize any hazard to the operator. However, the device generates voltages that can be dangerous. To assure safe operation, the operator should always plug the DOC into a Ground Fault Interrupter(GFI) outlet and carefully follow the instructions in this manual.
2 DOC Components The DOC is packed with the following components: Installation Digital Controller Power Cord (6 ft.) Valve/Sensor cable (20 ft.) Sensor probe Probe Installation Kit - Bulkhead connectors (2), bulkhead connector plugs (2), Solenoid Valve Valve installation Kit - Plastic tubing (8 in.), hose clamps (4) CAUTION: All installation steps must be completed before the DOC is connected to 110 VAC and power is applied. If the installation is to be modified in any way, power MUST be disconnected from the DOC. Installation of the Electronic Draw-off Controller is straight forward. However, due to the unique nature of each individual's manufacturing equipment, modifications to the installation instructions may be required. An overall installation diagram is shown in Figure 1. Installation is done in the following steps: Probe Installation The first step is to install the bulkhead connectors into the end pan. Two bulkhead connectors and two bulkhead caps/plugs are included. One bulkhead connector is installed near each draw-off valve. The bulkhead connectors should be located as close to the draw off outlets as possible so the probe is sensing the temperature near the valve. A 9/16 inch hole should be drilled into the pan so that the center of the hole is located halfway between the pan bottom and the normal syrup level, assuring that the probe is always fully submerged during operation. A bulkhead connector is then installed as follows: The washer is placed on the bulkhead connector and the bulkhead connector is placed through the pan hole. The bulkhead nut supplied has a slight relief cut into one face. The nut is tightened with the relieved face against the inside of the pan. The compression nut/ring assembly is placed on the probe so that when installed, the probe will protrude at least 4 inches into the pan. The probe is installed into the bulkhead connector and tightened FINGER tight only. The appropriate wrench is then used to tighten the nut an additional 3/4 turn. The bulkhead cap/plug is installed on the second bulkhead connector and tightened. Solenoid Valve Installation The solenoid valve is installed at the outlet pipe of the evaporation pan. Included in the valve installation kit is a length of plastic tubing and 4 hose clamps. Cut the plastic tubing into 2 sections. One length of plastic tubing is fitted over the inlet end of the valve (take care to note the flow direction marked on the valve) and secured in place with one of the hose clamps. The free end of the tubing is fitted
3 over the outlet pipe of the evaporator pan and secured with another hose clamp. User supplied fittings may be required to adapt the outlet pipe to the plastic tubing. The remaining length of plastic tubing is fitted over the outlet end of the valve and is secured with a hose clamp. The free end of this hose is placed into a suitable container. Probe/Valve Cable Installation The electrical connector of the probe is connected to the plug on the probe/valve cable, as shown in Figure 1. Note that this plug is polarized and will only fit into the probe receptacle one way. The electrical connection to the solenoid valve is made with the two lug connectors. The lug connectors should be firmly seated on the valve lugs with no exposed metal. The strain relief is then installed. The other end of the probe/valve cable is then plugged into the 9 pin connector on the back of the DOC and the locking screws are tightened until snug. Do not over tightened these locking screws.
4 Control Valve (Top View) Connect spade connectors to valve Probe/Valve Cable 20 feet long Temperature Probe Strain relief cable to valve with the plastic strain relief Bulkhead Connector Evaporation Pan 110 Power Cord Electronic Draw-off Controller Figure 1 - DOC Installation Diagram Digital Controller Location The digital controller is not designed to be exposed to the elevated temperatures that commonly occur near maple syrup evaporators. A 20 foot cable is supplied to make the connection between the controller and the valve/probe. For the longest possible controller life, it is recommended that the controller be placed at least 8 feet from the evaporator. The DOC may then be plugged into a 110 VAC outlet with Ground Fault Interrupt (GFI) protection. Peregrine Inc. requires the use of an GFI protected outlet for maximum operator safety.
5 Probe Handling When installing or removing the probe, never apply force directly to the probe electrical connector. Operation Normal Operation - The operation of the Electronic Draw-off Controller is as follows: 1) Turn DOC power switch (located on the back) to the ON position. (see Fig. 2) 2) If properly installed, the DOC will display 8888 for several seconds, and then display the measured temperature. The DOC does not attempt to accurately measure absolute temperature over a large range. The DOC was designed to measure small temperature changes around the syrup draw off temperature (about 219 degrees F) and consistently turn the control valve on and off about the set point. For temperatures above 200 F, the displayed temperature and the actual temperature are within a degree, but the change in temperature is accurately measured. For temperatures below 200 F, the displayed temperature may be in error by up to several degrees F, so in this range the DOC can be used only to indicate whether the temperature is rising or falling. The proper method of selecting the set point is to measure the syrup density as the temperature increases, and when the density is correct, adjust the set point to draw off at the displayed temperature. 3) Once the measured temperature is being displayed the unit is ready to be used. If 800.1, 800.2, 800.3, 800.4 or any single digit number is displayed instead of the measured temperature or the audible alarm sounds, the unit has detected a failure. Turn the unit OFF and refer to the Troubleshooting Section to determine if the operator can take any corrective action. Connect Power cable here Power switch S/N - 1234 Peregrine Inc. P.O. Box 464 Chanhassen MN 55317 Fuse No user serviceable parts inside. Danger: Hazardous voltage on Probe/Solenoid Connector Connect Probe/Solenoid Cable here Figure 2 - DOC Back Panel
6 Set Point Switch Operation Viewing the Set Point - Pressing the Set Point switch either up or down will allow the user to view the temperature at which the solenoid valve will be turned on. Changing the Set Point - Continuing to hold the Set Point switch in either the up or down position will cause the set point to change. The set point change rate is initially slow, and becomes more rapid if the operator continues to hold the switch in the same position. Changing the Power-Up Set Point - Once a new set point has been selected, and the unit turns the solenoid valve on and off five times, the current set point will be the set point that the unit automatically selects when it is turned on. The saving of the new power-up set point is indicated by a brief blanking of the display. Valve Switch Operation The valve control switch allows manual or automatic operation of the valve. The switch has three positions: 1) The AUTO position places the valve under automatic control of the DOC. 2) The OFF position turns the valve off and prevents the valve from turning on. (Note: If the set point is below the temperature of the syrup, the alarm may sound) 3) The ON position turns the valve on. The valve control switch allows manual control of the valve when necessary. For example, when the evaporation process is restarted with a batch of cool, "almost" syrup in the pan, most of the syrup in the pan may need to be drawn off at the same time. In this situation, the flow rate of the valve may be insufficient to allow the syrup to be satisfactorily drawn off under automatic control. In this case, it may be necessary to anticipate the draw off point and begin the draw off process manually. Operation Notes (1) Incorrect readings may occur if the probe/cable connection is exposed to moisture. Be sure that the probe/cable connection is free from condensation or drips. (2) When disconnecting the cable from the probe, be sure to pull only on the connectors with a gentle rocking motion; do not apply force to the probe tube. Incorrect disconnection may result in probe failure. Troubleshooting
7 The DOC is able to detect various types of failures. The self-test function does not detect all types of evaporator system failures, so the operator must be constantly on the alert for possible problems. Table 1 contains a list of the displayed error codes and a corrective action. The corrective actions may suggest additional tests, listed in Table 2, that require an operator supplied ohm meter. The DOC should be always disconnected from 110 VAC power when trouble-shooting is being done. If none of the corrective actions restore normal operation, the DOC should be returned to the supplier or manufacturer for repair. CAUTION: Voltages that can be harmful or be fatal to the operator may exist on the DOC cable and rear connector. Under no circumstances should the operator attempt any troubleshooting while the DOC controller is connected to 110 VAC power. Table 1. Error Codes and Corrective Actions Display Corrective Action Blank display Verify that power has been correctly supplied to the unit and fuse is intact. Replacement fuse size is 0.5 Amps, 250 Volts, 5 X 20 mm. 888.8 Lamp test mode entered briefly at startup. No corrective action required 800.0 The DOC is sensing a temperature above 300 F. Verify that the probe is not sensing a temperature above 300 F. 800.1 A failure associated with the electrical portion of the valve or its cable has been detected. Ensure that the cable is correctly connected to the valve and DOC. If problem persists, perform the valve and cable tests described in Table 2. 800.2 This indicates an open circuited probe. Verify that the temperature probe is connected properly to the DOC. Verify that all probe connectors are fully seated. If problem persists, perform the valve and cable tests described in Table 2. 800.3 This indicates a short circuited probe. Verify that the temperature probe has been connected properly to the DOC. If problem persists, perform the valve and cable tests described in Table 2. Buzz Only The over-temperature alarm has been tripped. Check for proper operation of the solenoid valve Any single digit Cycle power on the unit. If operation does not return to normal, the unit has failed and should be returned to the manufacturer for repair. The unit does not contain any user serviceable parts.
8 1 2 3 4 5 6 7 8 9 Figure 3 - Probe/Valve Connector, Cable end, Looking into the connector Table 2. Additional Trouble-shooting Actions Test Probe Test Valve Test Cable Test Action Disconnect the cable from the probe. The resistance across the probe connector should be between 80,000 and 120,000 ohms when the probe has cooled to room temperature (70 F). If the probe resistance is in this range then the probe is probably functional. Note the resistance of the probe varies significantly with temperature. Disconnect the cable from the valve. The resistance across the spades on the probe coil should be about 80 ohms. The valve actuator mechanism should be checked to assure that the valve can be manually opened and closed with ease. If the valve passes both of these tests successfully then the valve is probably functional. With the probe and valve connected, disconnect the cable from the DOC. The resistance between pins 6 and 7 on the cable connector (See Fig. 3) is the probe resistance (80,000 to 120,000 ohms at room temp.) and the resistance between pins 5 and 9 is the valve resistance (80 ohms). If either of these tests fail, there is a problem with the cable or its connectors. If this test is successful, the cable, valve and probe is functional. Limited Warranty The Draw-off Controller is warranted against defects in workmanship for 1 year from date of purchase. If this product is found to be defective Peregrine Inc.'s entire liability and your exclusive remedy is replacement or repair of the Draw-off Controller, at Peregrine Inc.'s option and no charge to you, provided that the Draw-off Controller has not been modified or damaged through misuse, abuse, accident, neglect, or mishandling.
9 Peregrine Inc shall not be liable for any direct, consequential or incidental loss or damage. The purchaser or user agrees to this warranty by purchasing or using the Electronic Draw-off Controller. Manufacturer Information Additional probes and valves can be obtained from the manufacturer or your distributor. If you unit needs repair during or after the expiration of the warranty period please contact your distributor or the contact listed below. Wes Hawkinson 6370 Pleasant View Cove Chanhassen, MN 55317 (952) 474-0318 wjhawk@ix.netcom.com