1500 Series INSTALLATION & SERVICE MANUAL 1500 Induction Control Relays When a source of alternating current is connected to the primary coil at terminals 3 and 4, the primary coil sets up a magnetic ţ ux which circulates through the shortest path following the lines of least resistance. As shown in Figure 1, this is through the lower bar of the laminated core on which the secondary coil is mounted. This magnetic ţ ux induces a voltage in the secondary or electrode circuit coil. No current can ţ ow in this coil, however, until the circuit is completed between the electrodes. Thus, the electrode circuit voltage being generated within the relay has no connection with the power line. The B/W 1500 induction relay utilizes the liquid as an electrical conductor to complete the secondary circuit between the upper and lower electrodes. Thus, when the liquid contacts the upper electrode, the resulting ţ ow of current in this circuit sets up a Principle of Operation bucking action in the lower bar of the core. This action tends to divert lines of magnetic force to the core legs and sets up an A B/W ţ oatless liquid level control system consists of a relay attraction that pulls the armature in to contact with the legs, as of the proper type, a holder designed to support one or more shown in Figure 2. This armature movement closes the electrode electrodes or probes in the liquid container, and the corrosion and load contacts. resistant electrodes themselves. In as much as all B/W induction relays are quite similar differing only in contact arrangement, the The lower contacts on 1500-C Relays (terminals 9 and 10) following description of how a 1500-C Relay functions on a connect the secondary circuit to ground when liquid contacts pump down control application will serve to explain the design, the upper electrode and act as a holding circuit to maintain the construction, and operating principles for the entire line. relay in its closed position until the liquid falls below the lower electrode. This holding circuit provides control of the relay over As shown in diagrams below, the laminated core of the relay is any desired range in the liquid level, depending on the distance shaped. The primary coil is assembled to the upper bar of the between the upper and lower electrodes. core, and the secondary coil for the electrode is placed on the lower bar. An armature located below the legs of the core is The ţ ow of current through the low energy secondary circuit connected to an insulated arm carrying the movable contacts. is very small and varies with the voltage of the secondary coil. When the armature is raised, these contacts close or open The secondary coil is selected to operate over the resistance the motor and electrode circuits, depending upon whether the of the liquid being controlled. Accordingly, since there is a wide contacts are normally open or closed. (Contacts shown normally range of secondary coils from which to choose, it is important open in this example). that complete information regarding the nature of the liquid be furnished when ordering B/W induction relays. 1500C Relay Used for Pump Down Control A.C. LINE A.C. LINE 3 4 3 4 FLUX FLUX 5 6 5 6 TO MOTOR STARTER TO MOTOR STARTER 7 8 7 8 9 10 9 10 ARMATURE ARMATURE PUMP START PUMP START ELECTRODE ELECTRODE GROUND: A GOOD DEPENDABLE GROUND: A GOOD DEPENDABLE GROUND RETURN GROUND RETURN CONNECTION TO THE CONNECTION TO THE PUMP STOP ELECTRODE LIQUID IS REQUIRED LIQUID IS REQUIRED PUMP STOP ELECTRODE Figure 1 - Secondary coil circuit open; armature down. Figure 2 - Secondary coil circuit closed; armature up. 1 Field Replaceable and Convertible Contacts Installation Instructions The Series 1500 Induction Relay provides circuit versatility by offering Relay: Install relay in level upright position. Connect wires a contact kit that allows Ţ eld conversions from N.O. to N.C. or N.C. from AC supply to terminals #3 and #4 on relay. Make sure to N.O. contact arrangements. This option also allows you to add or replace contacts (up to 3 per relay) as required for expansion of your power is of same rated voltage and frequency as shown liquid level control needs. for connection to primary coil on relay data plate. Relays draw 9 volt amperes. Electrodes: Install electrodes in tank or well by suspending them vertically from an electrode holder or some other suspending means. One electrode should be set at desired start level and one at desired stop level. For sewage or surface drainage sumps, make sure electrodes are hung far enough apart so that foreign matter ţ oating on water cannot foul electrodes. Size 18 or larger Type TW or THW wire is recommended for connection to the relay. Remove cover plate and armature CAUTION - Although the electrodes are connected to a low energy secondary coil output which has inherently low current, there may be up to 800 volts For a N.C. contact, For a N.O. contact, between the electrodes or from an electrode to install the moveable install the moveable ground. (See Secondary Coil Table.) Thus wiring and contact in the N.O. contact in the armature assembly electrodes should be installed to protect personnel armature assembly facing toward from accidental contact. facing toward the top the bottom of the of the relay. (away N.O. relay. (toward the from the armature) Ground: A system ground return circuit is required from the armature). indicated relay terminal to the liquid in order to complete N.C. the secondary circuit of relay. Conduit should not be used. Instead, connection should be made directly to uninsulated metal tank, or to metal pipe connected to tank below normal low liquid level. In wells, connect ground to pump or metallic water pipe. For concrete, wood, or Contact Kit Part No. 15-000001 insulated tanks, use an extra common electrode extending N.O. Contact N.C. Contact slightly below the longest operating electrode. Secondary Coil: Because the secondary voltage on all B/ W relays is an induced voltage generated within the relay For a N.O. contact, install the For a N.C. contact, install the itself, the secondary coil should never be connected to any stationary contacts facing toward stationary contacts facing in source of power. Voltage of the secondary coil installed on the bottom of the relay (toward the toward the top of the relay (away a given relay is determined by conductivity of liquid to be armature). from the armature). controlled. Load Connections: B/W relays are two-wire control devices having load contacts rated at 1 hp., single-phase, 115 or 230 volts AC or standard duty pilot rating up to 600 volts AC. In operation, load contacts act as a switch to open or close a circuit. Connecting them to an external load does not introduce a source of alternating current into the circuit. Accordingly, in making connections for direct operation of single-phase loads within rated capacity of relay, power CONTACT ARRANGEMENT CODE connections must be made as shown in relay wiring A B C D E F G H J 1 N.O. 2 N.O. 1 N.O. 3 N.O. 2 N.O. 1 N.O. diagram. 1 N.C. 1 N.C. 2 N.C. 1 N.C. 2 N.C. 3 N.C. TOP CONTACT 1 2 TERMINALS 1 & 2 R B/W CONTROLS 3 LINE VOLTAGE 4 To operate higher rated single-phase loads or three- 50/60 Hz MIDDLE CONTACT 5 6 Clawson, Michigan 48017 U.S.A. TERMINALS 5 & 6 R phase loads, a magnetic starter must be used. In making SECONDARY VOLTS 7 8 1500- connections to motor starter, follow directions given on BOTTOM CONTACT 9 10 TERMINALS 9 & 10 the starter wiring diagram for connecting two-wire control devices. 2 INDUCTION RELAY WIRING DIAGRAM AND OPERATION TYPICAL CONTACT APPLICATIONS DIRECT OPERATION PILOT OPERATION ARRANGEMENT 1 2 1 2 High Level Signal Control. Low 1500-A Relay LINE LINE A.C. 3 4 A.C. 3 4 Level Cutoff when wired in series VOLTAGE VOLTAGE Single Electrode Wiring LINE LINE 5 6 LOAD 5 6 TO ISOLATED with Stop button in 3-wire pushbut- Contact Arrangement LOAD CIRCUIT SECONDARY SECONDARY 7 8 7 8 VOLTAGE VOLTAGE ton stations. Remote, long distance 9 10 9 10 and low voltage manual control Normally Normally Holding applications, etc. Open Closed Circuit ELECTRODE ELECTRODE HOLDER HOLDER GROUND GROUND 1 0 0 ELECTRODE ELECTRODE LOAD ENERGIZED ABOVE THIS LEVEL LOAD CIRCUIT CLOSED ABOVE THIS LEVEL LOAD DE-ENERGIZED BELOW THIS LEVEL LOAD CIRCUIT OPEN BELOW THIS LEVEL Low Level Signal Control. High 1500-B Relay 1 2 1 2 Level Cutoff when wired in series Single Electrode Wiring LINE LINE A.C. 3 4 A.C. 3 4 VOLTAGE VOLTAGE LINE LINE with Stop button in 3-wire pushbut- Contact Arrangement 5 6 LOAD 5 6 TO ISOLATED LOAD CIRCUIT ton stations. Remote, long distance SECONDARY SECONDARY 7 8 7 8 VOLTAGE VOLTAGE and low voltage manual control Normally Normally Holding 9 10 9 10 applications, etc. Open Closed Circuit ELECTRODE ELECTRODE HOLDER HOLDER 0 1 0 GROUND GROUND LOAD DE-ENERGIZED ABOVE THIS LEVEL ELECTRODE LOAD CIRCUIT OPEN ABOVE THIS LEVEL ELECTRODE LOAD ENERGIZED BELOW THIS LEVEL LOAD CIRCUIT CLOSED BELOW THIS LEVEL Same as 1500-A Relay above 1500-C Relay 1 2 1 2 LINE LINE except that an additional Normally Single Electrode Wiring 3 3 A.C. VOLTAGE 4 A.C. VOLTAGE 4 LINE LINE 5 6 LOAD 5 6 TO ISOLATED Open contact is provided to permit Contact Arrangement LOAD CIRCUIT SECONDARY SECONDARY 7 VOLTAGE 8 7 VOLTAGE 8 simultaneous operation of different 9 10 9 10 types of secondary signal devices Normally Normally Holding GROUND GROUND in remote locations. Open Closed Circuit ELECTRODE ELECTRODE HOLDER HOLDER 2 0 0 LOAD ENERGIZED ABOVE THIS LEVEL LOAD CIRCUIT CLOSED ABOVE THIS LEVEL ELECTRODE ELECTRODE LOAD DE-ENERGIZED BELOW THIS LEVEL LOAD CIRCUIT OPEN BELOW THIS LEVEL High or Low Level Signal Control. 1500-D Relay 1 2 1 2 High of Low Level Cutoff when LINE LINE Single Electrode Wiring A.C. 3 4 A.C. 3 4 VOLTAGE VOLTAGE LINE LINE wired in series with Stop button in 3- Contact Arrangement 5 6 LOAD A 5 6 TO ISOLATED A LOAD CIRCUIT SECONDARY SECONDARY wire pushbutton stations. Can also 7 8 7 8 VOLTAGE VOLTAGE be used to interlock various types of Normally Normally Holding 9 10 LOAD B 9 10 TO ISOLATED B LOAD CIRCUIT signal devices. Open Closed Circuit ELECTRODE ELECTRODE HOLDER HOLDER GROUND GROUND 1 1 0 LOAD A DE-ENERGIZED ABOVE THIS LEVEL - B ENERGIZED ELECTRODE ELECTRODE LOAD CIRCUIT A OPEN ABOVE THIS LEVEL - B CLOSED LOAD A ENERGIZED BELOW THIS LEVEL - B DE-ENERGIZED LOAD CIRCUIT A CLOSED BELOW THIS LEVEL - B OPEN Same as 1500-B Relay above 1500-E Relay 1 2 LOAD A 1 2 TO ISOLATED A LOAD CIRCUIT A.C. except that an additional Normally LINE LINE Single Electrode Wiring LINE 3 4 A.C. 3 4 VOLTAGE VOLTAGE LINE Closed contact is provided to permit Contact Arrangement 5 6 LOAD B 5 6 TO ISOLATED B LOAD CIRCUIT SECONDARY SECONDARY simultaneous operation of different 7 8 7 8 VOLTAGE VOLTAGE types of secondary signal devices Normally Normally Holding 9 10 9 10 in remote locations. Open Closed Circuit ELECTRODE ELECTRODE HOLDER HOLDER GROUND GROUND 0 2 0 LOADS A & B DE-ENERGIZED ABOVE THIS LEVEL ELECTRODE LOAD CIRCUIT A & B OPEN ABOVE THIS LEVEL ELECTRODE LOADS A & B ENERGIZED BELOW THIS LEVEL LOAD CIRCUIT A & B CLOSED BELOW THIS LEVEL 1 2 1 2 1500-C Relay Pump Down Control for sewage and LINE LINE A.C. 3 4 A.C. 3 4 VOLTAGE VOLTAGE Two Electrode Wiring LINE LINE sump pumps, condensate return 5 6 LOAD 5 6 TO ISOLATED Contact Arrangement LOAD CIRCUIT system, etc. Low Level Cutoff for SECONDARY SECONDARY 7 8 7 8 VOLTAGE VOLTAGE submersible pumps. Normally 9 10 9 10 Normally Normally Holding closed Solenoid Valve Control for GROUND GROUND Open Closed Circuit discharging liquids from tanks, etc. ELECTRODE ELECTRODE HOLDER HOLDER 1 0 1 LOAD ENERGIZED ABOVE THIS LEVEL LOAD CIRCUIT CLOSED ABOVE THIS LEVEL ELECTRODE ELECTRODE LOAD DE-ENERGIZED BELOW THIS LEVEL LOAD CIRCUIT OPEN BELOW THIS LEVEL Pump Up Control for supply pumps 1 2 1 2 1500-D Relay on elevated tanks and towers, car- LINE LINE A.C. 3 4 A.C. 3 4 VOLTAGE VOLTAGE Two Electrode Wiring LINE LINE bonators, etc. High Level Cutoff for 5 6 LOAD 5 6 TO ISOLATED Contact Arrangement LOAD CIRCUIT SECONDARY SECONDARY pumps and valves. Normally closed 7 8 7 8 VOLTAGE VOLTAGE Solenoid Valve Control for plating 9 10 9 10 Normally Normally Holding tank and boiler make-up, etc. Open Closed Circuit GROUND GROUND ELECTRODE ELECTRODE HOLDER HOLDER 0 1 1 LOAD DE-ENERGIZED ABOVE THIS LEVEL LOAD CIRCUIT OPEN ABOVE THIS LEVEL ELECTRODE ELECTRODE LOAD ENERGIZED BELOW THIS LEVEL LOAD CIRCUIT CLOSED BELOW THIS LEVEL CAUTION: Electrodes are terminals of live electrical circuits and must be installed to prevent accidental contact by personnel. Control power must be disconnected before servicing. A GOOD DEPENDABLE GROUND RETURN CONNECTION TO THE LIQUID IS REQUIRED. 3 INDUCTION RELAY WIRING DIAGRAM AND OPERATION TYPICAL CONTACT APPLICATIONS DIRECT OPERATION PILOT OPERATION ARRANGEMENT 1 2 LOAD A 1 2 TO ISOLATED 1500-F Relay A Same as 1500-C Relay above LOAD CIRCUIT A.C. LINE LINE LINE 3 4 A.C. 3 4 VOLTAGE VOLTAGE Two Electrode Wiring except that additional Normally LINE 5 6 LOAD B 5 6 TO ISOLATED B Contact Arrangement LOAD CIRCUIT Open contact is provided to permit SECONDARY SECONDARY 7 8 7 8 VOLTAGE VOLTAGE simultaneous operation of second 9 10 9 10 Normally Normally Holding pump. Extra contact can also be GROUND GROUND Open Closed Circuit used for signal purposes if desired. ELECTRODE ELECTRODE HOLDER HOLDER 2 0 1 LOADS A & B ENERGIZED ABOVE THIS LEVEL LOAD CIRCUIT A & B CLOSED ABOVE THIS LEVEL ELECTRODE ELECTRODE LOADS A & B DE-ENERGIZED BELOW THIS LEVEL LOAD CIRCUIT A & B OPEN BELOW THIS LEVEL Pump Up or Pump Down Control for 1500-G Relay 1 2 LOAD B 1 2 TO ISOLATED B LOAD CIRCUIT A.C. LINE LINE LINE same applications listed above for 3 3 VOLTAGE 4 A.C. VOLTAGE 4 Two Electrode Wiring LINE 5 6 LOAD A 5 6 TO ISOLATED B/W 1500-C and 1500-D Relays. It Contact Arrangement A LOAD CIRCUIT SECONDARY SECONDARY 7 8 7 8 VOLTAGE VOLTAGE is also suitable for use in controlling 9 10 9 10 hydropneumatic tanks and motor- Normally Normally Holding GROUND GROUND ized valve installations. Open Closed Circuit ELECTRODE ELECTRODE HOLDER HOLDER LOAD A DE-ENERGIZED ABOVE THIS LEVEL - B ENERGIZED LOAD CIRCUIT A OPEN ABOVE THIS LEVEL - B CLOSED 1 1 1 ELECTRODE ELECTRODE LOADS A ENERGIZED BELOW THIS LEVEL - B DE-ENERGIZED LOAD CIRCUIT A CLOSED BELOW THIS LEVEL - B OPEN Same as 1500-D Relay above 1500-H Relay 1 2 LOAD A 1 2 TO ISOLATED A LOAD CIRCUIT A.C. except that additional Normally LINE LINE LINE 3 4 A.C. 3 4 Two Electrode Wiring VOLTAGE VOLTAGE LINE LOAD B Closed contact is provided to permit 5 6 5 6 TO ISOLATED Contact Arrangement B LOAD CIRCUIT SECONDARY SECONDARY 7 8 7 8 simultaneous operation of second VOLTAGE VOLTAGE 9 10 9 10 pump. Extra contact can also be Normally Normally Holding used for signal purposes if desired. GROUND GROUND Open Closed Circuit ELECTRODE ELECTRODE HOLDER HOLDER LOADS A & B DE-ENERGIZED ABOVE THIS LEVEL LOAD CIRCUIT A & B OPEN ABOVE THIS LEVEL 0 2 1 ELECTRODE ELECTRODE LOADS A & B ENERGIZED BELOW THIS LEVEL LOAD CIRCUIT A & B CLOSE BELOW THIS LEVEL CAUTION: Electrodes are terminals of live electrical circuits and must be installed to prevent accidental contact by personnel. Control power must be disconnected before servicing. A GOOD DEPENDABLE GROUND RETURN CONNECTION TO THE LIQUID IS REQUIRED. Catalog Numbering System 1500 A L1 S7 X OC Catalog Contact Line Voltage Secondary Typical Liquids Enclosure Type Additional Section Arrangements Coil Voltage Options L1 110-120 Volts OC Open Chassis 50/60 HZ S1 12 Volts A.C. Metallic circuits X None Normally N1 NEMA 1 L2 208-240 Volts S2 24 Volts A.C Metallic circuits General M Manual Open Closed 50/60 HZ Purpose Push Button S3 40 Volts A.C. Acid or caustic solutions: Milk; A1 0 L3 440-480 Volts Brine and salt solutions; Plating N4 NEMA 4 B0 1 50/60 HZ solutions; Buttermilk; Soups Weather Proof C2 0 L4 550-600 Volts S4 90 Volts A.C Weak acid or caustic solutions: N4X NEMA 4X 50/60 HZ Beer; Baby foods; Fruit juices Corrosion D1 1 Resistant L5 Dual Voltage S7 220 Volts A.C. Sewage; Most water-except very E0 2 120/240 Volts soft; Pottery slip; Water soluble oil N7 NEMA 7 F3 0 50/60 HZ solutions; Starch solutions ClassiŢ ed G2 1 Location S8 360 Volts A.C. Very soft water; Sugar syrup H1 2 N12 NEMA 12 Oil Tight J0 3 S9 480 Volts A.C. Steam condensate; Strong alcohol solutions All contacts rated at: S11 800 Volts A.C. Demineralized or distilled water 25 Amp Resistive at 120, 240, or 480 VAC 1 HP Single Phase at 120 or 240 VAC Heavy Duty Pilot 120 to 600 VAC 2 Amp Resistive at 120 VDC 10 Amp Resistive at 48 VDC 4 operation. This condition can be corrected by checking to see that proper Service Instructions electrode connections are made. Excessive accumulation of dirt, grease or other deposits on the electrodes can also result in noisy relay operation - in CAUTION which case periodic cleaning will eliminate the problem. Be sure to disconnect relay control power before servicing electrodes 2. Low Secondary Voltage - If resistance of the liquid being controlled is or electrode holders. at the upper end of the sensitivity range of the relay secondary coil, noisy operation may result. Sensitivity may be increased slightly by interchanging B/W relays are designed and built to require a minimum of service in the Ţ eld. the ground and lower electrode connections at the relay. If this does not Each one is tested and adjusted at the factory to insure positive operation and correct the condition, the relay should be replaced with one having a higher should not be altered or tampered with prior to installation. If a relay does not voltage secondary coil. operate properly after it has been installed, the following information will be helpful in determining the probable cause. C. One Level Operation If a relay operates at one level only - starting and stopping at one electrode, A. Relay Will Not Pull In check the following: If relay will not pull in when liquid contacts upper electrode, failure to operate is probably caused by one of the following conditions: 1. Electrode Wires - If wires between relay and electrodes are interchanged, relay will not operate over range in level but from upper electrode only. To 1. Power Failure - A power failure to relay can be caused by broken wire, correct, simply reverse connections - either at relay or at electrodes. blown fuse, an open switch, loose screw, corroded connection, etc. Check for power failure with voltmeter or test light directly on relay line terminals (No.3 2. Ground Connection - Poor ground connection will prevent holding circuit and 4 on all B/W relays). Also check voltage at motor starter line terminals from functioning and cause relay to operate from the upper electrode only. and overload heaters on motor starter to be sure they have not tripped. This can be easily corrected by making sure that ground connections conform with Installation Instructions. 2. Open Coils - Coils used in B/W relays very rarely fail unless struck by lightning or subjected to some severe over-voltage condition. To check coils, 3. Holding Circuit - If the holding circuit is not closing, the relay will operate disconnect electrode connections from relay terminals, apply line voltage to from the upper electrode only. Since the holding circuit contact carries only the primary coil, and touch both ends of secondary coil with an insulated a small current, a slight Ţ lm of grease or dirt can sometimes prevent proper jumper wire. Relay should pull in when the jumper is connected and fall out closure. To correct, rub contact surface with a clean paper. Do not use sand when the jumper is removed. Failure to do so indicates that one of the coils is paper or emery cloth. open. If an open coil is found, contact dealer or the factory for a replacement relay. 4. Upper Electrode Lead - A ground in lead wire to the upper electrode will cause relay to operate from lower electrode only. This condition can be 3. Poor Ground Connections - B/W induction relays that operate from a checked out as described below. single electrode i.e., Types 1500-A, C, B, E and D will not function unless a good dependable ground connection is made to complete the secondary D. Relay Will Not Drop Out circuit from one end of the secondary coil through the electrode and liquid, If relay will not drop out when liquid falls below lower electrode, check the and back through ground to the other side of the secondary coil. If such a relay following points: does not operate when liquid contacts the electrode, check ground connection to be sure it complies with installation instructions. 1. Lower Electrode Lead - A ground in the lead wire from relay to lower electrode will prevent relay from dropping out on low liquid level. If distance 4. Broken Wires - A broken wire from relay to either electrode will prevent from holder to relay is relatively short, the best way to check for a ground is relay from operating. Broken wires can be checked by shorting the upper and to connect a replacement wire from relay to the electrode holder outside the lower electrode leads together at the electrode holder. If relay fails to pull in, conduit and test the relay for operation. If it drops out properly it is safe to one or both of the electrode leads is open. The individual leads can then be assume that a ground exists in the original lower electrode lead wire. checked by running a temporary wire from the relay to holder outside conduit. If relay pulls in, it may be assumed that break is between the holder and the If relay is located a considerable distance from electrode holder, check for electrodes. This can be checked by shorting between the electrode tips with ground as follows: Disconnect power to relay. Remove wires from terminals an insulated jumper. in electrode holder and allow them to stick up to eliminate possibility of contacting a grounded part. Then turn on power to relay. If relay pulls in, 5. Low Secondary Voltage - If the secondary coil voltage is too low for the a short is indicated between the electrode leads, from both electrodes to resistance or conductivity of the liquid being controlled, the relay will not pull ground, or secondary coil is shorted internally. If relay does not pull in, short in - or it will buzz and chatter before pulling in. In either case, the relay should secondary coil with piece of insulated wire by bridging between relay terminal be replaced with one which has a higher voltage secondary coil. (See Table.) connections for upper and lower electrodes. Relay should pull in when this If in doubt about proper coil selection, furnish factory with details on liquid - or connection is made and drop out when connection is broken. If relay does not send sample for test. drop out, a short to ground is indicated in lower electrode lead. This ground may not be enough to pull in relay, but it can be sufŢ cient to hold relay in once 6. Fouled Electrodes - Accumulation of dirt, grease or other deposits on it has been closed in normal operation. the upper electrode will insulate it and prevent relay from pulling in. If this occurs, the electrodes should be inspected and cleaned at regular intervals If any of these conditions exist, disconnect power to relay and replace as required to eliminate the difŢ culty. If unusual quantities of oil, grease, or grounded wires. sludge and encountered, the electrodes can be mounted inside a pipe that is ţ ushed with clean water. A 4” pipe should be used - with the bottom located 2. Electrode Holder - Excessive dirt or moisture over insulation at electrode below the lowest water level, and vent holes provided at top so that the level holder or electrodes can cause faulty relay operation. Interior of electrode inside and outside the pipe will be the same. A small ţ ow of water entering the holder and its underside should be kept clean and dry. Conduit connections top of the pipe will cause an outward ţ ow of water from the bottom of the pipe should be made so that no condensation can enter holder. Underside of and prevent undesirable material from entering. Thus, the electrodes have a vertically mounted holders should never come in contact with the liquid. clear surface on which to operate and will stay clean. Insulated rod electrodes should be used with horizontally mounted holders. 7. Electrodes Too Short - It is possible for an installation to be completed Electrodes should be kept relatively clean and free of dirt or grease. Check in which the upper electrode is suspended at a point where the liquid cannot them periodically to make sure they do not become fouled with ţ oating debris make contact. All installations should, of course, be checked to make sure or insulating deposits. that proper electrode lengths are provided. 3. Length of Lead Wires - On installations with excessive distance - over 900 B. Noisy Relay Operation feet - between relay and tank, relay may tend to hold in due to capacitance in If the relay functions properly but is noisy in operation, it could be caused by electrode lines and fail to drop out when liquid leaves lower electrode. Since the following: there are a number of ways to achieve reliable long distance control, complete information regarding such applications should be submitted to factory for 1. Poor Electrode Connections - If wire suspended electrodes are used recommendations. and have either been lost or not properly connected resultant increase in resistance is secondary circuit may cause relay to buzz or chatter in 5 Conductive Liquids With nearly 50 years of experience B/W has compiled a history With the exception of products such as oil, gasoline, animal of applications in most major industries around the world. If you fats and other similar products, most liquids and some moist have questions regarding the proper relay selection, write us, bulk materials have sufŢ cient conductivity to use B/W level phone us, or send a sample for test. Chances are that we have detecting relays. The Series 1500 relay can be used on liquids the answer for you. with resistance up to about 90,000 ohm-cm (conductivity to 11 micromho/cm). Typical Liquids For liquids with higher resistance the B/W Series 52 relay The following recommendations are satisfactory for general described in Catalog Section 5200 must be used for applications use, but because the conductivity of liquids varies greatly with up to 12 megohms resistance. The vapor above some liquids concentration, purity, temperature and other factors, some is considered an explosive hazard and in these cases the B/W applications may require a different selection. A number of Series 53 relay with FM approved intrinsically safe sensing the products listed are produced as solids such as crystals or circuit should be used. See Catalog Section 5300. powers, and our relay selection is based on the normally used commercial solutions of these materials. Liquids such as milk and beer, and some pharmaceutical products will foam during processing. The liquid phase is always a better conductor than the foam, and when the interface level is to be detected, the relay sensitivity must be carefully selected and it would be well to check the factory for our recommendation. Liquid Description ........................Secondary Coil Liquid Description ........................Secondary Coil Acetic Acid Formaldehyde ........................................ Use 5200-H Relay - Up to 75% ....................................... 90 Volt Formic Acid - 75 to 90% ........................................ 220 Volt - Up to 75% ....................................... 90 Volt - Glacial ............................................. Use 5200-H Relay - 75 to 90% ........................................ 220 Volt Acetone .................................................. Use 5200-H, 5300 or 5400 Relay Glycerine (Glycerol) ................................ Use 5200-H Relay Acids Hydrochloric Acid .................................... 40 Volt - General ........................................... 40 or 90 Volt Hydroţ uoric Acid - Anhydrous ....................................... Use 5200-H Relay - Up to 20% ....................................... 220 Volt Alcohols .................................................. Use 5200-H, 5300 or 5400 Relay - Above 20% ...................................... 40 Volt Alkalies Hydroţ uorsilicic Acid .............................. 90 Volt - General ........................................... 40 or 90 Volt Hydrogen Peroxide ................................. Use 5200-H, 5300 or 5510 Relay - Anhydrous ....................................... Use 5200-H or 5400 Relay Jams & Jellies ........................................ 360 Volt Alum Solutions ....................................... 220 Volt Juices - Fruit & Vegetable ...................... 40 or 90 Volt Aluminum Sulphate ................................ 90 Volt Lemon Oil Essence ................................ Use 5200-H Relay Aluminum Hydroxide .............................. 90 Volt Lignite ..................................................... 800 Volt Amino Acids ............................................ 90 Volt Lithium Chloride ..................................... 40 Volt Ammonia-Anhydrous Liquid ................... Use 5200-H Relay Magnesium Hydroxide ............................ 90 Volt Ammonium Chloride ............................... 40 Volt Mayonnaise ............................................ 220 Volt Ammonium Hydroxide (Ammonia) ......... 220 Volt Methanol ................................................. Use 5200-H or 5300 Relay Ammonium Nitrate .................................. Use 5300 or 5400 Relay Methyl Ethyl Keystone (MEK) ................. Use 5200-H Relay Ammonium Sulphate .............................. 220 Volt Milk ......................................................... 40 Volt Baby Foods ............................................ 90 Volt Molasses ................................................ 220 Volt Barium Chloride ...................................... 40 Volt Muriatic Acid ........................................... 40 Volt Barium Nitrate ........................................ 40 Volt Mustard .................................................. 40 Volt Beer ......................................................90 Volt Nitric Acid................................................ 40 or 90 Volt Black Liquor ............................................ 40 Volt Orange Juice .......................................... 90 Volt Blood ...................................................... 220 Volt Paper Stock ............................................ 220 Volt Borax Penicillin ................................................. 220 Volt - Up to 10% ....................................... 220 Volt Phosphoric Acid ...................................... 40 Volt - Greater than 10% ............................ 90 Volt Plating Solutions ..................................... 40 or 90 Volt Boric Acid ............................................... 220 Volt Salts - Chemical ..................................... 40 or 90 Volt Bread Dough .......................................... 90 Volt Sodium Carbonate (Soda Ash) ............... 90 Volt Buttermilk................................................ 24 or 40 Volt Sodium Chloride (Table Salt) .................. 40 Volt Cadmium Chloride .................................. 40 Volt Sodium Hydroxide (Caustic Soda) ......... 40 Volt Cake Batter ............................................ 220 Volt Sodium Hypochlorate ............................. 40 Volt Calcium Chloride .................................... 40 Volt Sodium Silicate (Water Glass) ................ 90 Volt Calcium Hydroxide ................................. 220 Volt Soups ..................................................... 40 Volt Carbolic Acid Starch Solutions ..................................... 220 Volt - Up to 90% ....................................... 220 Volt Sugar - 90 to 100% ...................................... Use 5200-H or 5400 Relay - Low Concentrations ........................ 220 Volt Catsup .................................................... 90 Volt - High Concentrations ........................ 360 Volt Caustic Soda (Sodium Hydroxide) ......... 40 Volt Sulphuric Acid ......................................... 40 Volt Cement Slurry ........................................ 220 Volt Vinegar ................................................... 90 Volt Chromic Acid .......................................... 40 Volt Water Citric Acid................................................ 40 or 90 Volt - Sea .................................................. 40 Volt Coffee ..................................................... 90 Volt - Ordinary Potable ............................. 220 Volt Condensate - Ordinary Soft ................................... 360 Volt - Ordinary Water ................................ 480 Volt - Ordinary Condensate ...................... 480 Volt - D.I. Water ........................................ Use 5200-H Relay - PuriŢ ed Distilled .............................. 800 Volt or 5200-H Relay Corn Syrup ............................................. 480 Volt - PuriŢ ed Deionized ........................... Use 5200-H Relay Corn - Cream Style ................................. 90 Volt Zinc Chloride .......................................... 40 Volt Ethylene Glycol ...................................... Use 5200-H or 5400 Relay Ferric Chloride ........................................ 90 or 220 Volt Ferrous Sulphate .................................... 220 Volt 511 Copyright 2005 by AMETEK Automation & Process Technologies 1500.M4R 1080 N. Crooks Road, Clawson, MI 48017 Toll Free 800-635-0289 02/05.Z145 10M Phone 248-435-0700 Fax 248-435-8120 www.AMETEKAPT.com 6