Thermostats and Accessories Thermostats and Accessories ® SERIES EHG ........................................................641 SERIES EHG SL10 ................................................643 ST10 and ST207....................................................647 Bulb and Capillary ................................................649 Low Liquid Level Sensors....................................653 Protective Wells....................................................654 ® WATLOW 639 ® 640 WATLOW Thermostats and Accessories ® SERIES EHG Many applications requiring a fixed temperature set point have relied on mechanical thermostat devices (thermostats) for thermal control. But, thermostats are inadequate for many applications because of the long-term reliability issues such as 100,000 cycle rating and poor temperature control. ® The SERIES EHG thermal solution includes a compact temperature control, thermocouple sensor and power switching device that are integrated into the heater’s power cord. The SERIES EHG reduces system costs and substantially extends the life over conventional thermostat solutions. The evolution of miniature microprocessor technology and Watlow switching technology allowed the development of a small versatile temperature control and thermocouple Durable housing with built-in strain relief sensor that can be integrated with Watlow silicone rubber heater products. This device senses the temperature via • Protects electronics input from a thermocouple strategically placed on the • Low risk of mechanical damage heater mat. The microprocessor is programmed prior to Manufactured with proven Watlow components shipment with the customer’s application specific set • Assures reliable system performance point. This results in quick delivery of a custom integrated system. Applications The small mass of the thermocouple provides superior response to changes in process temperature and allows • Aerospace composite repair for higher watt density silicone rubber heater designs. • Foodservice equipment Depending on the specific application, Watlow’s power • Freeze protection switching design can extend life up to 40 times greater than thermostats. These features result in an integrated • Life sciences custom set point temperature control product with • Semiconductor superior life span, faster heat-up rates and improved • Telecommunications accuracy. The SERIES EHG system has been tested to over four million cycles at rated amperage. Features and Benefits Long operational life • Improves system reliability Tight temperature control • Assures process accuracy Small sensor footprint • Fits with almost any heater • Responds quickly to temperature changes • Controls high watt densities in low mass applications Reduced system cost • A single EHG control can be configured with multiple heaters to reduce system cost Pre-wired, in line control • Simplifies installation • Two wire power connection ® WATLOW 641 Thermostats and Accessories SERIES EHG Technical Information Specifications SERIES EHG Versus Thermostat (typical application) Operational ® • SERIES EHG silicone rubber heater UL recognized to 90.00 428°F (220°C) operating temperature 85.00 •Factory programmed fixed set point 80.00 • On-off control with 6°F (3°C) switching hysteresis • Temperature band LED indicator ON between 75.00 -68 and +68°F (–20 and +20°C) of set point Electrical 70.00 • Voltage rating: 120 or 240VÅ(ac) – 30/+10%, 50/60Hz 65.00 2 • Silicone rubber heater watt densities up to 80 W/in 2 (12.5 W/cm ) dependent on application temperature 60.00 ® • SERIES EHG system UL recognized to 10A max. 55.00 Sensor • Type K thermocouple 50.00 0.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 90.00 Mechanical Elapsed Time (min.) Thermostat • Control dimensions 3.75 in. (95 mm) long by EHG 1.75 in. (45 mm) diameter Dimensions • Heater per silicone rubber heater specifications Agencies ® • Silicone rubber heater: UL recognized File #E52951 • SERIES EHG control: TUV File DE 3-3068 to ® ® EN 61010-1:2001, UL File E43684 to UL 873 temperature indicating and regulating equipment Environmental 3.75 in. (95 mm) • Control operating temperature range 32 to 128˚F (0 to 70˚C) • Control storage temperature range -40 to 158˚F (–40 to 70˚C) Contact your Watlow representative for custom configurations. 1.85 in. (47 mm) Integrated SERIES EHG System Versus Integrated Thermostat System Integrated EHG System Integrated Thermostat System SERIES EHG Benefit Life comparison at Tested to greater than Rated 100,000 cycles Longer product life of rated amperage 4,000,000 cycles with SERIES EHG system and 10A load high reliability in application Switch hysteresis 6°F (3°C) 15°F (8°C) SERIES EHG system will provide superior process control Improved response time 6°F (3°C) typical 25°F (14°C) typical SERIES EHG system will respond reduces overshoot on changes in temperature faster start-up than thermostat Warranty 2 years on material 1 year on material Warranty can be extended because and workmanship and workmanship of superior SERIES EHG life Zero Cross Switching SERIES EHG has Random switching during Reduces possibility of electrical zero cross switching sign wave cycle mechanical interference (EMI) ® WATLOW 642 Thermostats and Accessories ® SERIES EHG SL10 ® The EHG SL10 is a key component in a powerful system that integrates a heater, an adjustable set point temperature controller, high/low temperature alert, power switching device and a high temperature safety limit. This agency recognized controller/safety limit meets ® UL 1998 and CE 60730 requirements. The optional display/communications module can be easily upgraded and added in the field to provide digital display indication, ® adjustment of set point, RS485 Modbus communications and other Human Machine Interface (HMI) features. This system allows you to purchase only what is needed for your application. The easy to install, compact design, inherent reliability and integrated limit functions make this controller a tremendous value. The controller is designed for easy ® integration with Watlow heaters simplifying engineering, reducing component count on new equipment and decreasing cost of ownership. For original equipment manufacturers (OEMs), CE, Semi-S2 compliance and Health check diagnostics ® UL recognition will reduce time and costs necessary • Monitors maximum heater process temperature, for global agency testing and validation. maximum ambient temperature and thermocouple operation Features and Benefits • Provides health check signal to inform operator that Process controller and safety limit in one package ® the process is working correctly • Meets UL 1998 and CE 60730 requirements Universal power supply • Eliminates the need for a thermal fuse on a heater • Allows an input of 85 to 264VÅ(ac), 50/60Hz • Eliminates replacement of heater when fuse fails • Provides safe control of up to 2400 watts with Optional display/communications module 10 amperes switching in both controller and safety limit • Allows easy upgrade on to base device Can be switched from on-off and PID algorithm • Offer low cost field upgrade • Increases product life (on-off control is default) • Provide easy, snap-on installation • Offers selectable PID control algorithm for tighter Accurate and flexible temperature process temperature uniformity controller 1 Universal ⁄8 turn mounting bracket • Replaces problematic bi-metal thermostats with • Allows mounting to most surfaces accurate electronic temperature process controller • Provides flexible mounting—either horizontally • Allows easy change of process parameters or vertically Ambient operating temperature range 32 to 158°F (0 to 70°C) Applications • Increases reliability when mounting in harsh Foodservice equipment temperature environments or in close proximity • Warming and serving equipment to heaters • Food holding cabinets Integrated high/low temperature alert signal relay Life sciences • Provides dry contact output to activate external alarm • Laboratory equipment or process function • Medical equipment • Signals control status with three integrated LEDs Packaging • Allows a signal of up to two amperes 30Vı(ac/dc), Form A to alert if process temperature is out of • Heat sealing bars range limits • Hot glue application equipment Semiconductor processing • Gas delivery lines ® WATLOW 643 Thermostats and Accessories SERIES EHG SL10 Technical Information Specifications SERIES EHG Versus Thermostat (typical application) Operational 90.00 • Two, Type K thermocouple inputs - process temperature control and safety limit 85.00 • Process temperature output - 10A NO-ARC relay • Safety limit alarm - 10A relay 80.00 • High/low temperature alert - 2A 30Vı(ac/dc), Form A 75.00 (single pole, normally open contact) • On-off temperature controller algorithm, upgraded via 70.00 communications to PID algorithm (min. cycle time 65.00 30 seconds) Standard Molex connectors 60.00 • Controllers are integral to the heater and are supplied by Watlow 55.00 Power 50.00 0.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 90.00 • Isolated universal power supply 85 to 264VÅ(ac), Elapsed Time (min.) Thermostat 50/60Hz EHG • Up to 2400 W with 10A switching capability Dimensions NO-ARC Relay 3.496 in. (88.80 mm) • 10A switching • 4.5 million cycles Environmental • Ambient operating temperature range 32 to 158°F 2.196 in. (0 to 70°C) (55.78 mm) Agency Approvals ® ® • UL 1998/ C-UL • CE 60730 Base Unit • Semi-S2 1.907 in. 2.486 in. (48.44 mm) (63.14 mm) 2.161 in. 1.582 in. (40.18 mm) (54.89 mm) Without Optional Module With Optional Module Switching Device Comparison Chart T-Stat Solid State Relay Watlow NO-ARC Relay Amperage at 77°F (25°C) 10A 10A 10A Amperage at 158°F (70°C) 10A De-rate significantly and add 10A heat sink and air cooling Output device life at 10A Rated 100,000 at 158°F (70°C) Greater than 10 million cycles Greater than 4.5 million cycles at 77°F (25°C) at 158°F (70°C) ® WATLOW 644 Thermostats and Accessories SERIES EHG SL10 Technical Information (Continued) EHG SL10 Software Reduces System Complexity and Cost With the addition of an optional communication module, the EHG SL10 can be managed, monitored and manipulated via software. Change set points, label devices, change tuning parameters, check health status and much more all with the click of a key. Mounting Bracket The EHG SL10 can be “daisy-chained” for gas line and other assemblies. The EHG SL10 mounting bracket lets you mount the controller in any of four angles. ® WATLOW 645 Thermostats and Accessories SERIES EHG SL10 Technical Information (Continued) Optional Upgrade Modules These upgrade modules are easy to install because there is no need to reconfigure, rewire or reorder the base unit. No technician is needed for the installation, which creates a seamless, cost-efficient system that can be upgraded. Diagnostics Ability to 3-Digit ® Memory Change Field 7-Segment User Modbus Control Temperature Adjustable LED Display Diagnostic Interface RTU Parameters Parameters Set Point Illuminated LED’s Software Communication RS 485 Base Unit Optional Display Module Optional Commun- ication Module Optional Display and Commun- ication Module ® WATLOW 646 Thermostats and Accessories ST10 and ST207 Temperature Sensors ST-207E ® Watlow offers several styles of sensors for use with flexible heaters. These sensors are available as preset or adjustable thermostats, thermocouples, thermistors, RTDs or thermal fuses. They can be integrally mounted (encapsulated in silicone rubber) to sense the temperature of either the part or the heater sheath. The thermostats can also be ordered separate from the heater, allowing direct control of your process temperature, if desired. ST-207 Pre-Set Thermostats Several styles of non-adjustable, pre-set thermostats are available from Watlow. Thermostats separate from the ST-10 heater are encapsulated in silicone rubber, and are available with standard 12 in. (305 mm) leads unless otherwise specified. Thermocouples, thermistors, RTDs and thermal fuses are usually mounted to the heater under a vulcanized protective cap of silicone rubber sheath material. This drawing shows a typical mounting style for a thermocouple. Note: Precise part temperature control with preset thermostats requires prototyping and field testing. Ref. Ref. 3 / in. 16 3 11 /8 in. /16 in. (4.8 mm) (9.5 mm) (17.5 mm) 3 3 /4 in. / in. 4 (19 mm) (19 mm) 3 /4 in. (19 mm) 3 1 1 /4in. 1 / in. 4 (45 mm) (32 mm) 1 2 /2 in. (64 mm) 1 1 /2in. 1 1 /2in. (38 mm) (38 mm) T-10 T-207 Thermocouple Pre-Set Thermostats (Non-Adjustable) Agency Approvals Thermostat Maximum Volts Temperature Settings Model Watts AC Available °F (°C) UR cUR VDE T-10 600/960 120/240 *125-300±10 (50-149±5) yes yes yes T-207 1500 120/240 40/55±8 (4/13±4.4) yes yes yes 1500 120/240 60/75±8 (16/24±4.4) yes yes yes 1500 120/240 95/110±8 (35/43±4.4) yes yes yes 1500 120/240 145/160±8 (63/71±4.4) yes yes yes Notes: • T-10 thermostats are manufactured for specific preset temperatures. • When ordering a pre-set thermostat separate from the heater, Available in 25°F increments. simply add the prefix S to the model number. (Example: ST-10) • Other temperature ranges and voltages are available on special order. See next page. Minimum quantities apply, contact your Watlow representative • Snap action preset temperatures on the T-207 are close/open settings. before ordering. ® WATLOW 647 Thermostats and Accessories ST10 and ST207 Temperature Sensors (Continued) Adjustable Thermostats Adjustable Thermostats Separate From Heater The B-200 thermostat features a maximum rating of 1500 watts at 120/240VÅ(ac). The following temperature 5 1 ⁄8 in. ranges are available: (41.3 mm) • Model B-200-2: 100 to 500°F (40 to 260°C) • Model B-200-3: 25 to 330°F (-5 to 165°C) 7 2 ⁄8 in. The B-200 thermostat can be integrally mounted to the (73 mm) heater with a bonded protective cap of silicone rubber sheath material. 11 1 ⁄16" ⁄2 in. Separate Heater Accessories Available (13 mm) B-200 From Stock Pre-Set Thermostats Separate From Heater These are offered to allow direct control of your process The Model B-200 adjustable thermostat can be ordered temperature, so you’re not limited to controlling only the as a separate item. The same model numbers and heater temperature when using stock heaters. Pre-set temperature ranges indicated under Adjustable thermostats are encapsulated in silicone rubber with Thermostats are available. When ordering, simply note standard 12 inch leads. that you want the B-200 separate from the heater. The same temperature ranges, ratings and sizes are available on these thermostats. When ordering, add “S” prefix to the model number to indicate “separate” item. (Examples: ST-10 and ST-207) ® Standard leads are 12 in. (305 mm) 18 gauge UL 1180 black leads. 0.50 in. (13 mm) 0.34 in. (8.6 mm) 2.25 in. (57 mm) 1.75 in. (45 mm) 1.25 in. (32 mm) 0.218 (5.5 mm) Dia. Typ. (13 mm) 0.50 in. 0.50 in. 1 in. (25 mm) (13 mm) Ref. Note: For direct control of air temperature as is required in enclosure heating applications, specify thermostat model number ST-207E. This is 1 a modified ST-207 mounted on ⁄32 inch thick G-10 circuit board with the thermostat’s metal cap exposed to sense air temperature. ® WATLOW 648 Thermostats and Accessories Bulb and Capillary Thermostats regulate temperature in non-critical applications. They sense temperature, within a preset range and cycle heaters on and off to maintain the set point. Thermostats may be mounted inside a terminal enclosure or remote mounted (separate from the heater assembly). If using a remote mounted thermostat, be sure to order the sufficient capillary tube length to permit installation. ® All Watlow thermostats are normally closed circuit and either single-pole, single-throw (SPST) or double pole, single-throw (DPST). They can be used with or without an enclosure. Thermostat selection should be based on temperature range, capillary tube length and sensor bulb size (diameter/length). Remote Mount Thermostat Assemblies Warning Remote mounted thermostat Do not use thermostats for high-limit sheath protection. assemblies can be supplied with the following enclosures: Thermostats fail in a closed circuit mode and will not cut • General purpose (NEMA 1) power to the heaters. Limit control should be provided by • Moisture resistant (NEMA 4) an isolated, redundant sensor and control system of the appropriate type, design and installation. • Explosion resistant (NEMA 7) Thermostats are precalibrated at the factory. No • Explosion/moisture resistant (NEMA 7/4) adjustment, other than selecting the desired operating • Dust resistant (NEMA 12) temperature, is required. All wiring should be performed Pilot Light by qualified personnel and comply with the National An optional pilot light gives visual indication whether the Electrical Code and other applicable state and power supplied to the heating element(s) is on or off. local codes. To order, please specify suffix code PL11. To help assure you select the correct thermostat, as well as install and wire it properly, we have put together a few Thermostat Conversion Kits helpful hints. Schematics are provided for interconnecting Kits are available to convert a heater’s general thermostats to single- and three-phase heaters. purpose (NEMA 1) terminal enclosure to accept either a single- or double-pole thermostat. The kit contains all the necessary parts to change out the existing terminal enclosure cover and mount the thermostat inside. These are hardware and wiring kits only. 1 1 Single-pole conversion kit covers 1, 1 ⁄4 , 2 and 2 ⁄2 inch NPT screw plugs. To order, specify code K492-000-35-(thermostat type). 1 Double-pole conversion kit covers 2 and 2 ⁄2 inch NPT screw plugs. To order, specify code K492-000-34- (thermostat type). Celsius Dial Scale Thermostats are shipped with Fahrenheit (°F) dial scales. If your application requires a Celsius (°C) scale, order the optional dial face. To order, specify code CD. Scale will match thermostat temperature range. ® WATLOW 649 Thermostats and Accessories Bulb and Capillary Technical Information Application Hints Pilot Duty Wiring (Continued) • Locate the thermostat where ambient temperatures SPST, 3-phase delta do not exceed 150°F (65°C). 1 L1 • Mount the thermostat in an enclosure that is 1 L2 compatible with the surrounding environment. • Immerse the entire sensing bulb in the media being 1 L3 heated. • Make sure the sensing bulb is mounted away from the SPST heating element(s) to negate any undue influence on the sensing bulb’s temperature “reading.” 120VÅ(ac) P • Keep the capillary tube insulated from electrical connections. • Do not use a thermostat for high-accuracy SPST, 3-phase wye temperature sensing. Use an appropriate 1 L1 thermocouple, RTD or thermistor and temperature control. • Do not use thermostats as a primary power switching 1 L3 device. Use a disconnect switch or circuit breaker to 1 L2 cut power when servicing. SPST • Interconnect the thermostat to the heater only if: 120VÅ(ac) - The heater has one circuit P - The heater’s ampere draw is lower than the thermostat’s rated ampacity at prescribed voltage. • Interconnect either a single- or double-pole thermostat Interconnected Wiring with a single-phase heater when the supply voltage SPST, 1-phase does not exceed 277VÅ(ac) for SPST or 480VÅ(ac) for DPST. SPST 1 L1 • Only interconnect three-phase delta heaters to DPST thermostats. P • Use a single-pole thermostat for pilot duty where the 1 L2 thermostat is not interconnected with the heater, or heater exceeds the volt/amp rating. DPST, 1-phase DPST 1 L1 Pilot Duty Wiring SPST, 1-phase P 1 L1 1 L2 1 L2 DPST, 3-phase delta DPST SPST 1 L1 120VÅ(ac) P P 1 L2 1 L3 ® WATLOW 650 Thermostats and Accessories Bulb and Capillary Technical Information (Continued) NEMA 7 Single-Pole Thermostats with Enclosures NEMA 1 Single- and Double-Pole 4⁄Ä in. (117.5 mm) 3¼ in. 3¼ in. (83 mm) (2) ½ in. (83 mm) 2⁄%& in. 3⁄"# in. (13 mm) (54.8 mm) (84.1 mm) 5⁄"# in. 2!⁄"# in. (134.9 mm) (55.6 mm) 6!⁄Ä in. 3 in. (161.9 mm) (76 mm) NEMA 7 Double-Pole 5'!⁄"# in. 7¾ in. (147.6 mm) (197 mm) 7 in. (178 mm) 6 in. NEMA 4 and 12 Double-Pole (152 mm) 6⁄ÄÅ in. (166.7 mm) (13 mm) ½ in. 6½ in. (165 mm) 6⁄ÄÅ in. (166.7 mm) 6¼ in. (164 mm) !⁄"# in. 8¾ in. (222 mm) (11.1 mm) 4¼ in. Order With Cross-Reference For (108 mm) Replacement Thermostat This Number in. 202-0-21-1 (small knob) 1 6 (152 mm) 202-0-21-2 (small knob) 202-0-21-2MB 202-0-21-4 2 202-0-21-5 2A NEMA 4 and 12 Single-Pole 202-0-21-3 3 3⁄ÄÅ in. 202-0-21-8 (small knob) 202-0-21-8M (81 mm) 202-0-21-6 3A 202-0-4-2 4 2¾ in. ⁄ÄÅ in. 202-0-4-6 5 (70 mm) (88 mm) 202-0-4-17 5A 202-0-4-5 7 (2) 0.218 in. 202-0-4-16 7A 4⁄" in. (5.5 mm) Dia. Holes (111.1 mm) 202-0-3-1 8 202-0-3-3 9 202-0-1-13 10 202-0-29-2 11 2#$⁄ÄÅ in. 202-0-41-2 (small knob) 12A (74.6 mm) If you only have the thermostat code number use this cross-reference chart. ® WATLOW 651 Thermostats and Accessories Bulb and Capillary ® ® Technical Information (Continued) Thermostat Control Temperature Ampacity @ Bulb Bulb Capillary Terminal Code Est. Net Mode Type Range Differential Line Voltage Diameter Length Length Type No. Wt. °F (°C) ˚F (˚C) 120 240 277 480 in. (mm) in. (mm) in. (mm) lbs (kg) 3 On-off Single- 30-110 (0-40) 8 (0) 25 25 22 — 0.250 (6) 4 ⁄4 (121) 18 (455) 1 1 (0.4) 1 Temp Pole 30-250 (0-120) 15 (8) 25 25 22 — 0.250 (6) 3 ⁄4 (85) 18 (455) #12 AWG 2 1 (0.4) 1 Control Single- 30-250 (0-120) 15 (8) 25 25 22 — 0.250 (6) 3 ⁄4 (85) 84 (2135) Stranded 2A 1 (0.4) 3 Throw 175-550 (80-290) 26 (14) 25 25 22 — 0.250 (6) 3 ⁄8 (85) 18 (455) Leads 3 1 (0.4) 3 (SPST) 175-550 (80-290) 26 (14) 25 25 22 — 0.250 (6) 2 ⁄4 (70) 84 (2135) 3A 1 (0.4) 3 300-700 (150-350) 12 (7) 25 25 —— 0.375 (10) 3 ⁄4 (95) 60 (1525) 10 1 (0.4) 3 60-160 (15-70) 19 (10) 30 30 30 20 0.250 (6) 4 ⁄8 (110) 14 (355) #8-32 12A 1 (0.4) 1 Double- 30-110 (0-40) 12 (7) 30 30 30 10 0.375 (10) 6 ⁄4 (160) 36 (915) 4 2 (0.9) 1 Pole 60-250 (15-120) 12 (7) 30 30 30 10 0.375 (10) 4 ⁄2 (115) 48 (1220) #10-32 5 2 (0.9) 1 Single- 60-250 (15-120) 12 (7) 30 30 30 10 0.250 (6) 6 ⁄2 (165) 48 (1220) Screw Lug 5A 2 (0.9) 7 Throw 100-550 (40-290) 22 (12) 30 30 30 10 0.375 (10) 3 ⁄8 (100) 48 (1220) 7 2 (0.9) 1 (DPST) 100-550 (40-290) 22 (12) 30 30 30 10 0.250 (6) 7 ⁄16 (179) 48 (1220) 7A 2 (0.9) 1 On-off (DPST) 60-250 (15-120) 12 (7) 30 30 30 — 0.250 (6) 6 ⁄2 (165) 48 (1220) #10-32 8 2 (0.9) with 100-550 (40-290) 22 (12) 30 30 30 — 0.188 (8) 12 (305) 48 (1220) Screw Lug 9 2 (0.9) 1 Manual (SPST) 350⑨ (180) — 30 30 20 — 0.250 (6) 3 ⁄2 (90) 36 (915) #10-32 11 1 (0.4) Reset Screw Lug ®  UL recognized only ⑨ Fixed temperature setting RAPID RAPID SHIP SHIP • RS - Same day shipment up to 15 pieces Ordering Information To order, complete the code number to the right with the information below: Example: 2 W LTB ___ ___ ___ Thermostat Code Number See stock chart above Enclosure (Remote Mount Only) S= General purpose (NEMA 1) W= Moisture resistant (NEMA 4) E= Explosion resistant (NEMA 7) E/W = Explosion/moisture resistant (NEMA 7/4) D= Dust resistant (NEMA 12) Options CD = Celsius dial scale CB = Chrome bezel 3 LTB = Liquid-tight brass fitting ( ⁄8 in. - 18 NPT) PL11= Pilot light ® WATLOW 652 Thermostats and Accessories Low Liquid Level Sensors ® The Watlow low liquid level sensor can protect a heating system by sensing when a liquid drops below a predetermined level. This is accomplished by locating the sensor at the minimum desired liquid level in the tank or vessel. The sensor’s ASTM Type J thermocouple output can be connected to a variety of controls, alarms and limit protection devices. To provide an additional margin of protection, the Type J thermocouple makes this low liquid level sensor respond considerably faster than conventional capillary bulb thermostats. To order, specify code number BCN5J1SJ. Application Hints • Only use sensor in non-flammable liquids that are ® compatible with the Incoloy sheath and 304 stainless General Purpose (NEMA 1) Enclosure steel screw plug. 3 /4 in. NPT Conduit Opening • Application should tolerate sheath temperature at limit 1 in. /2 ® ® FIREROD (13 mm) set point. Cartridge Heater Dia. • The time delay between the low liquid level condition on-set, and the sensor’s ability to signal the control 1 in. (13 mm) /2 No-Heat device should be adequate to protect the heater(s). 1 5 /2 in. (140 mm) See Installation and Maintenance Instructions for details. Controller Recommendation • Use Watlow Safety Limit Temperature Controller Availability SERIES 142 (Code number 142A-3605-1300). This controller features compact sub-panel mounting and is Stock: Same day shipment ® sealed against ambient environment. UL recognized
Modified Stock : Five to seven working days for limit protection (UL 991, “Tests For Safety-Related Made-to-Order: Four to six weeks Controls Employing Solid State Devices”). Options, complexity and quantity may affect availability and lead times. Contact your Watlow representative. Specifications Screw plug: 1 in. (25 mm) NPT
Stock units with catalog options. Plug material: 304 stainless steel ® Sheath material: Incoloy 2 2 Watt density: 13 W/in (2 W/cm ) Watts: 100 Volts: 120VÅ(ac) 1 Immersed length: 5 ⁄2 in. (140 mm) Thermocouple: ASTM Type J Est. ship. wt.: 2 lbs (1 kg) ® WATLOW 653 Thermostats and Accessories Protective Wells Protective wells isolate and protect thermostat bulbs and other temperature sensors (thermocouples, RTDs or thermistors). They allow inserting the sensing element sufficiently into the media being heated without being damaged. Steel or stainless steel protective wells are available 1 in three lengths. They are supplied with ⁄2 inch NPT 3 mounting and ⁄8 inch-18 NPT internal thread for mating to a liquid-tight bushing (LTB). All units are stock. To order, specify the appropriate code number from the stock table. Protective Wells 3 in. Internal /8 NPT Plug and Immersed Est. Ship. 0.500 in. O.D. Thermowell B Dimension Code Wt. Material in. (mm) Number lb (kg) Immersed Length 12 (305) PWS12 1 (0.5) 1 1 in. NPT /2 B ± /4 in.(6 mm) Steel 24 (610) PWS24 2 (1.0) 36 (915) PWS36 2 (1.0) Stainless 12 (305) PWSS12 1 (0.5) Steel 24 (610) PWSS24 2 (1.0) Availability 36 (915) PWSS36 2 (1.0) Stock: Same day shipment
Modified Stock : Five to seven working days Made-to-Order: Three weeks Options, complexity and quantity may affect availability and lead times. Contact your Watlow representative.
Stock units with catalog options. ® 654 WATLOW