1、Form 829 (09.11) 2011 SOR Inc. 1/16 The Ultrasonic Point Level Switch indicates liquid presence/absence within a sensor cavity. Two piezoelectric crystals face each other across the sensor cavity. One crystal transmits an ultrasonic signal; the other crystal receives the signal. When the sensor cavi
2、ty is empty, the receiver detects a weak signal because air is a poor conductor of ultrasonic waves. With the failsafe switch in the “HI” position, the normally open relay contacts remain open, and the Liquid Level LED is not lit. When process liquid fills the sensor cavity, the receiver detects a s
3、trong signal because liquids are good conductors of ultrasonic waves. With the failsafe switch in the “HI” position, the normally open relay contacts are closed, and the Liquid Level LED is lit. The Failsafe Slide Switch reverses the relay actuation. However, the liquid level LED is lit only when th
4、e relay is energized. The sensor monitor circuitry (standard on 721 and 722 series switches only) constantly monitors sensor integrity and opens the normally open contacts of the sensor monitor relay in the unlikely event of a sensor failure. The relay is energized when the sensor is operating prope
5、rly. Model 711 through 722, 24 VDC, 120 VAC or 240 VAC power supply with notch-type, or viscous sensors Ultrasonic Point Level Switch (One and Two Point)General Instructions Registered Quality System to ISO 9001:2008 Design and specifications are subject to change without notice. For latest revision
6、, go to NOTE: If you suspect that a product is defective, contact the factory or the SOR Representative in your area for a return authorization number (RMA). This product should only be installed by trained and competent personnel. Table of Contents PC Board Arrangement .2 Sensor Installation 3-4 E
7、lectrical Connection .5 Sensor Monitor Connection .6 One Point Remote Cable Connection . 7-8 Time Delay Adjustments . 10 Pump Logic Accessory . 11 PC Board Field Replacement . 11 Sensor Test Procedure . 13 Replacement Fuses 13 Spare Parts 13 T roubleshooting . 14 Control Drawings . 15-162/16 Form 82
8、9 (09.11) 2011 SOR Inc. PC Board Arrangement 9-Position Terminal Block (Reverse Side) Ground (Earth) Power Supply DPDT Level Indication Relay Contact Factory-sealed sensitivity pot No adjustment required Liquid Level Indication LED Sensor Lead Connection J1 (remote cable connection A) Sensor Lead Co
9、nnection J2 (remote cable connection T) Replacable Fuse(s) Failsafe Slide Switch 6-Position Terminal Block (Reverse Side) DPDT Sensor Monitor Relay Contact Off Delay Timer Adjustment On Delay Timer Adjustment 9-Position Terminal Block (Reverse Side) Ground (Earth) Power Supply DPDT Level Indication
10、Factory-sealed sensitivity pot No adjustment required Liquid Level Indication LED Sensor Lead Connection J1 (remote cable connection A) Sensor Lead Connection J2 (remote cable connection T) Replacable Fuse(s) Failsafe Slide Switch Sensor Monitor LED Models beginning with 71 Models beginning with 72
11、Standard 316SS and Teflon Notch-Type sensors and 316SS Viscous sensors are available for use with the point level switch. Extreme care must be taken when installing units with Teflon sensors. See installation instructions beginning on page 3. Viscous and Teflon sensors are available in one point con
12、figuration only.Form 829 (09.11) 2011 SOR Inc. 3/16 Sensor Installation Notch-Type Sensor (Series 37 - N) Series 370 Ultrasonic Level Sensors can be mounted by inserting the sensor through a fitting in a vessel, or the sensor may be suspended over an open sump or basin. Tank or Vessel Make sure that
13、 the sensor can be fully inserted and tightened without interference from obstructions inside the tank or vessel. (See) Apply suitable sealant to the process connection to prevent process leakage. Do not use the sensor base as a handle to tighten the process connection. One Point Horizontal Sensor M
14、ounting (Series 371 Notch-Type) When tightened securely, the sensor cavity must face sideways for optimum drainage when process liquid level drops below the sensor cavity. An alignment mark X stamped on a wrench flat (or on the dry face of a flange below the housing) shows sensor cavity orientation.
15、 (See(andy ) Notch-Type Sensors Optimum drainage occurs when the X mark is located at 3 or 9 oclock. The sensor must project through a tank fitting so that the sensor cavity is at least 1” beyond the inner wall of the tank. (Seeand) DO NOT weld any part of this instrument. Irreparable damage may be
16、done to Te on sensors by turning Metal hex and Te on hex separately. Always rotate Metal hex and Te on hex simultaneously. Do not apply more than 10 in. lbs. of torque to either hex during installation! Te on Notch Sensor (Metal sensor may vary) Always turn Teflon hex & Metal hex together when insta
17、lling sensor into process. Sensor Base Hub No Obstructions Apply thread sealant4/16 Form 829 (09.11) 2011 SOR Inc. Sensor Installation Notch-Type Sensor Mounting Alignment mark shown at 3 oclock Alternate position: 9 oclock 1 inch minimum Open Sump or Basin Do not suspend the unit by rigid conduit i
18、nstalled in the electrical hub. When installing the unit over an open sump or basin, use a suitable bracket to support the instrument. Locally Supplied Bracket Open Sump or Basin Viscous Sensor (Series 371-V) Vertical or horizontal (flange only) mounting is supported for the viscous sensor. A 3” (76
19、.2mm) diameter minimum opening is required for insertion. An alignment mark X stamped on the dry face of the flange below the housing shows sensor cavity orientation. (See ) Optimum drainage occurs when the X mark is located at 6 oclock. Take care during installation to prevent damage to the sensor
20、end. Slight bending of the sensor may result in loss of sensitivity due to misalignment of the ultrasonic crystals. DO NOT weld any part of this instrument. NOTE: The instrument must be positioned so that over ow does not ood electrical housing (see )Form 829 (09.11) 2011 SOR Inc. 5/16 5.9 0.23 5.9
21、0.23 Cof flange Bottom View Viscous Sensor with 8-Hole Flange Alignment mark (other side) position at 6 oclock (typ.) Bottom View Viscous Sensor with 4-Hole Flange 62.1 2.44 (typ.) Viscous Sensor Cavity Orientation 76.2 minimum 3.00 opening required (typ.) L Electrical Connection Electrical power mu
22、st be disconnected from explosion proof models before the cover is removed. Failure to do so could result in severe personal injury or substantial property damage. Ensure that wiring conforms to all applicable local and national electrical codes and install unit(s) according to relevant national and
23、 local safety codes. A nine-position terminal strip provides connections for DPDT Liquid Level Relay Contacts, Line Power and Ground. Terminal positions are labeled on the green insulator card as shown in . Two point sensors have twin PC boards marked “Upper” or “Lower” for their matching sensor cav
24、ities. A. Liquid Level Relay Contact Terminals Before making connections to the Liquid Level Relay Contact Terminals on the nine-position terminal strip, determine the fail-safe mode best suited for the application. Locate fail-safe slide switch. (See and ) Refer to the continuity chart for the sele
25、cted fail-safe mode ( ) when making connections to the Liquid Level Relay Contact Terminal positions. When the unit is used as an FM approved Low Water Level Limit Switch, the Fail-safe Slide Switch must be set to the HI position as shown in the upper half of . B. Line Power Terminals Terminals are
26、provided for incoming power leads on the nine- position PC board terminal strip. Supply voltage for each PC board is printed on the green insulator card. Make sure that the available line voltage matches the devices power supply. C. Ground Terminals The housing and the PC Board must be connected to
27、ground. Ground (earth) screws are provided on the nine-position PC board terminal strip and on the housing floor. If extra clearance is required for connection to the ground screw on the housing floor, the PC board can be removed and reinstalled according to PC Board Field Replacement on page 11.6/1
28、6 Form 829 (09.11) 2011 SOR Inc. Sensor Monitor Connection - Models 721 and 722 only B Nine-Position Liquid Level Relay Terminal Strip A NC1 C1 NO1 NO2 C2 NC2 L1 N GND NC1 C1 NO1 NO2 C2 NC2 + - GND NC1 C1 NO1 NO2 C2 NC2 L1 L2 GND 24VDC 120 VAC 240VAC C Any loss of the physical or electrical ultrason
29、ic sensor integrity causes instantaneous de-energizing of the DPDT sensor monitor relay. (See ) Two point sensors have one sensor monitor relay for each sensor cavity. A six-position terminal strip provides connections for each set of DPDT sensor monitor relay contacts. Terminal positions are labele
30、d on the green insulator card(s). The sensor monitor is continuously on duty whenever the instrument is powered. It does not require external initiation and it is not initiated at programmed intervals. If the sensor monitor indicates a fault, see Troubleshooting on page 14. Fail-safe Mode Switch Pos
31、ition Sensor Condition Liquid Level Relay Contact A Continuity Chart Relay energized on high level Liquid above sensor NC1 C1 NO1 NO2 C2 NC2 Relay Energized Liquid below sensor NC1 C1 NO1 NO2 C2 NC2 Relay De-engergized Relay energized on low level Liquid above sensor NC1 C1 NO1 NO2 C2 NC2 Relay De-e
32、nergized Liquid below sensor NC1 C1 NO1 NO2 C2 NC2 Relay Energized Relay Continuity Chart Sensor Status Sensor Monitor Relay Contact Continuity Chart FunctioningNC1 C1 NO1 NO2 C2 NC2 Relay Energized Sensor/Electronics Malfunction Loss of Power Supply NC1 C1 NO1 NO2 C2 NC2 Relay De-energizedForm 829
33、(09.11) 2011 SOR Inc. 7/16 One Point Remote Cable Connection - Models 711R1 and 721R2 Only Install conduit between the sensor base and the electronics housing to provide a raceway for sensor extension cables. (See ) The sensor base and the electronics housing are suitable for use in Class I Groups C
34、 Class II Groups E, F Divisions 1 & 2 hazard- ous locations. All conduit and fittings used for the installation must equal or exceed this rating to maintain the explosion proof integrity of the assembly. Ensure that wiring conforms to all applicable local and national electrical codes and install un
35、it(s) according to relevant national and local safety codes. Fishing the Sensor Extension Cables Two sensor extension cables are supplied. Both ends of the cables are terminated and labeled at the factory. Use care to avoid damaging the factory installed coax connectors while fishing the sensor exte
36、nsion cables through the conduit. Pull cables from the sensor base so that the free ends follow the fish through the conduit. (See ) Leave enough cable in the electronics housing to make PC board connections. Sensor Coax Connections Inside Sensor Base Inside the sensor base, the remote interconnect
37、board rests in a plastic holder. Slide the interconnect board up. Attach the extension cables to the interconnect board as follows:Connect the long sensor cable (A) to IN 1. Connect the short sensor cable (T) to IN 2. Attach the extension cables to the interconnect board as follows:Connect cable A t
38、o OUT 1.Connect cable T to OUT 2. (See ) Control Board Seeand Protect factory installed plugs Remote Interconnected Board SeeSensor Base Conduit must meet Class I Groups C & D: Class II Groups E, F & G Divisions 1 & 2 Electronics Housing8/16 Form 829 (09.11) 2011 SOR Inc. Discharge the Sensor Temper
39、ature changes which occur during shipment may result in a small electrical charge inside the sensor crystals. This charge is harmless to humans, but may result in damage to the electronics if the sensor is plugged in before it is discharged. To discharge the sensor, touch a wire to each sensor Short
40、 each center conductor to the shell to discharge sensor crystals. connector so that the center conductor and outside shell make contact. (See ) Plug in Connections Inside Electronics Housing Plug sensor extension cables onto the PC board as follows:Connect cable A to J1.Connect cable T to J2. (See a
41、nd ) Power to the electronics must be disconnected before removing the cover of the sensor base in a hazardous area. Connect extension lead T to OUT 2 Remote Interconnect Board located inside sensor base Connect sensor leads to IN 1 and IN 2 Connect extension lead A to OUT 1 OUT connections are loca
42、ted on the opposite side of the board from the IN connections. Do not use positions 3 and 4 to connect wires. A T A T One Point Remote Cable Connection - Models 711R1 and 721R2 Only Install conduit between the sensor base and the electronics housing to provide a raceway for sensor extension cables.
43、(See ) The sensor base and the electronics housing are suitable for use in Class I Groups C Class II Groups E, F Divisions 1 & 2 hazardous locations. All conduit and fittings used for the installation must equal or exceed this rating to maintain the explosion proof integrity of the assembly. Ensure
44、that wiring conforms to all applicable local and national electrical codes and install unit(s) according to relevant national and local safety codes.Form 829 (09.11) 2011 SOR Inc. 9/16 Coax Connections Inside Sensor Base Inside the sensor base, a remote interconnect board rests in a plastic holder.
45、Slide the interconnect board up. Attach the sensor coax connectors to the interconnect board as follows (See ):Connect cable A to IN 1. Sensor cavity A (upper)receiver crystalConnect cable B to IN 3. Sensor cavity B (lower) receiver crystalConnect cable T to IN 2. (Transmitter crystals) Attach the e
46、xtension cables to the interconnect board as follows:Connect cable A to OUT 1.Connect cable B to OUT 3.Connect cable T to OUT 2. Avoid mismatched connections which could render the unit inoperative. Protect factory installed plugs Sensor base Conduit must meet Class I Group C Class II Groups E ,F &
47、G: Division 1 & 2 Electronics Housing Fishing the Sensor Extension Cables Three sensor extension cables are supplied. Both ends of the cables are terminated and labeled at the factory. Use care to avoid damaging the factory installed coax connectors while fishing the sensor extension cables through
48、the conduit. Pull cables from the sensor base so that the free ends follow the fish through the conduit. (See ) Leave enough cable in the electronics housing to make PC board connections. Connect extension lead T to OUT 2 Remote Interconnect Board located inside sensor base Connect T lead to IN 2 Co
49、nnect A lead to IN 1 Connect B lead to IN 3 Connect extension lead B to OUT 3 Connect extension lead A to OUT 1 OUT connections are located on the opposite side of the board from the IN connections. Do not use position 4 to connect wires. B A T B A T10/16 Form 829 (09.11) 2011 SOR Inc. Plug in Connections Inside Electronics Housing Discharge the sensor per instructions on page 8. Attach the PC board connectors according to Figure . Note that cable T can be connected to J2 on either the upper or the lower PC Board. Electrical pow
