Echotel® Model 940/941 Ultrasonic Level Switch DESCRIPTION Echotel Model 940 and 941 Ultrasonic Level Switches are compact integral units that utilize pulsed signal technology to perform high or low level measurement in a wide variety of liquid applications. These switches feature a 316 stainless steel tip-sensitive transducer that is offered in a variety of NPT, flanged, and sanitary process connections. The compact electronics are completely encapsulated just above the process fitting. The Model 940 offers a 1-amp SPDT relay output. The Model 941 has a mA current shift output. Model 940/941 with Tri-Clamp® fitting FEATURES • Pulsed electronics for excellent performance in difficult process conditions and superior immunity from sources of electromagnetic noise • Tip-sensitive transducer gap provides reliable operation by draining viscous liquids and shedding foam in turbulent applications • Safety Integrity Level (SIL) data (FMEDA analysis) is available. Model 940 is suitable for SIL 2 loops. Model 941 is suitable for SIL 1 loops. • Extremely compact unit is easily installed in areas where access space is limited • 1 amp SPDT relay output (940), or mA current shift (941) output • No calibration or configuration necessary Model 940/941 with 3⁄4" NPT Model 940/941 with ANSI flange APPLICATIONS The Model 940/941 can be applied in a wide variety of high or low liquid level applications, pump protection, and fill line monitoring as shown in the diagram at the left. These compact units can also be installed in the interstitial space between two tank walls for fluid leak detection. Filling line High alarm Small size and simplicity of installation make these units ideal for OEM skids as a low cost, yet high performance level measurement solution. They are also the perfect replacement for older floats, conductivity switches, and tuning forks. Low alarm High alarm Low alarm Pump Pump protection Typical Mounting Orientations TECHNOLOGY Ultrasonic energy detects the presence or absence of liquid in a tip sensitive transducer gap. The principle behind contact ultrasonic technology is that high frequency sound waves are easily transmitted across a transducer gap in the presence of liquid, but are attenuated when the gap is dry. The transducer uses a pair of piezoelectric crystals that are encapsulated in epoxy at the tip of the transducer. The crystals are made of a ceramic material that vibrates at a given frequency when subjected to an applied voltage. The transmit crystal converts the applied voltage from the electronics into an ultrasonic signal. When liquid is present in the gap, the receive crystal is able to sense the ultrasonic signal from the transmit crystal and convert it back to an electrical signal. This signal is sent to the electronics to indicate the presence of liquid in the transducer gap. When there is no liquid present, the ultrasonic signal is attenuated and is not detected by the receive crystal. Customer provided conduit Transmit crystal Ultrasonic transducer Receive crystal Figure 1 Ultrasonic signal transmission across transducer gap SPECIFICATIONS Electrical: Power Supply: 12–35 VDC Power Consumption: Less than 1 Watt Signal Output: Model 940: SPDT relay, 1 amp @ 30 VDC, 0.5 amp @ 125 VDC, 0.5 amp @ 150 VAC Model 941: Dry Gap: 8 mA (±1 mA), Wet Gap: 16 mA (±1 mA) Cabling: 18" (457 mm) flying leads of 18 AWG wires Repeatability: 0.078" (2 millimeters) Response Time: 1 ⁄2 second typical Environmental: Ambient Temperature: -40° to +185° F (-40° to +85° C) Process Temperature: -40° to +185° F (-40° to +85° C) Maximum Pressure: 2000 psig (138 bar) for 1" (3 cm) and 2" (5 cm) transducers 1500 psig (103 bar) for transducers longer than 2" (5 cm) Shock ANSI/ISA-S71.03 Class SA1 Vibration ANSI/ISA-S71.03 Class VC2 AGENCY APPROVALS AGENCY APPROVED MODELS PROTECTION METHOD AREA CLASSIFICATION FM & CSA 94X-XXXX-XXX Non-Incendive Class I, Div. 2,Groups A,B,C, & D Class II, Div. 2, Groups E,F, & G Class III, Type 4X, IP 66, T4 941-XXXX-XXX Intrinsically Safe Class I, Div. 1,Groups A,B,C, & D Class II, Div. 1, Groups E,F, & G Class III, Type 4X, IP 66, T4 These units have been tested to EN 50081-2 and EN 50082-2 and are in compliance with the EMC Directive 89/336/EEC. 2 SPECIFICATIONS Inches (mm) 3/4" NPT 3/4" NPT 3/4" NPT 4.13 (105) 3.9 (99) 3.9 (99) Actuation length for NPT process connection Actuation length for Tri-Clamp fitting 0.25 (6) Actuation length for ANSI flange 0.25 (6) 0.25 (6) ∅ .875 (22) ∅ .875 (22) ∅ .875 (22) Model 940/941 with Tri-Clamp fitting Model 940/941 with 3⁄4" NPT Model 940/941 with ANSI flange MODEL NUMBER Models available for quick shipment, usually within one week after factory receipt of a purchase order, through the Expedite Ship Plan (ESP) BASIC MODEL NUMBER 940 941 Low cost compact ultrasonic level switch with SPDT relay output Low cost compact ultrasonic level switch with current shift output AGENCY APPROVAL 1 7 FM/CSA Intrinsically Safe & Non-Incendive (Model 941 only) FM/CSA Non-Incendive (Model 940 only) PROCESS CONNECTIONS 11 22 23 33 43 3T 4T 3 ⁄4" NPT 1" BSP (G1)* 1" 150# ANSI RF flange* 1.5" 150# ANSI RF flange* 2" 150# ANSI RF flange* 1"/1.5" Tri-Clamp 16 AMP fitting* 2" Tri-Clamp 16 AMP fitting* * Minimum actuation length of 2 inches or 5 centimeters ACTUATION UNITS E M English (inches) Metric (centimeters) ACTUATION LENGTH 1 to 100 inches (Example: 4 inches = 004) 3 to 250 centimeters (Example: 6 cm = 006) Available ESP length = 1" (001) 9 4 Note: Optional NEMA 4 cast aluminum junction box assembly 052-7012-XXX is available from the factory. 3 QUALITY The quality assurance system in place at Magnetrol guarantees the highest level of Magnetrol’s quality assurance system is registered to ISO 9001 affirming its commitment quality throughout the company. Magnetrol is committed to providing full customer satisfaction both in quality products and to known international quality standards providing the strongest assurance of product/service quality available. quality service. ESP Several Echotel switches are available for quick shipment, usually within one week after factory receipt of a purchase order, through the Expedite Ship Plan (ESP). Expedite Ship Plan Models covered by ESP service are color coded in the selection data charts. color coded model number codes (standard dimensions apply). ESP service may not apply to orders of ten units or more. Contact your local representative for lead times on larger volume orders, as well as other products and options. To take advantage of ESP, simply match the WARRANTY All Magnetrol electronic level and flow controls are warranted free of defects in materials or workmanship for one full year from the date of original factory shipment. If returned within the warranty period; and, upon factory inspection of the control, the cause of the claim is determined to be covered under the warranty; then, Magnetrol will repair or replace the control at no cost to the purchaser (or owner) other than transportation. Magnetrol shall not be liable for misapplication, labor claims, direct or consequential damage or expense arising from the installation or use of equipment. There are no other warranties expressed or implied, except special written warranties covering some Magnetrol products. 5300 Belmont Road • Downers Grove, Illinois 60515-4499 • 630-969-4000 • Fax 630-969-9489 • www.magnetrol.com 145 Jardin Drive, Units 1 & 2 • Concord, Ontario Canada L4K 1X7 • 905-738-9600 • Fax 905-738-1306 Heikensstraat 6 • B 9240 Zele, Belgium • 052 45.11.11 • Fax 052 45.09.93 Regent Business Ctr., Jubilee Rd. • Burgess Hill, Sussex RH15 9TL U.K. • 01444-871313 • Fax 01444-871317 Copyright © 2009 Magnetrol International, Incorporated. All rights reserved. Printed in the USA. Performance specifications are effective with date of issue and are subject to change without notice. Magnetrol & Magnetrol logotype and Echotel® are registered trademarks of Magnetrol International. BULLETIN: 51-136.2 EFFECTIVE: September 2009 SUPERSEDES: August 2006