Assessments - 3, GPA: 3.7
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4 I sic, pit ¡тшшт booie SALES REFERENCE (Supersedes PK428-4) PK428-5 161-048628-001 DATE OCTOBER, 1987 Chromalox General Purpose Industrial Thermostat Catalog Number PIT with Rain-Tight Enclosure Catalog Number PIT-EP with Explosion-Proof Enclosure Type PIT (rain-tight) a UL Listed Not a fail-safe device Type PIT-EP (explosion-proof) Specifications — Tabie A Catalog Number (RainTight; Catalog Number (Explosion Proof) Temp. Range (°F) Sensitive Buib with 10' Capillary V' &3. Nominal* Difieren' fiai Í°F) "A” Dia. “B” Lgth. PIT-15 P1T-15EP 0-150° .290" 21/2" 6 PIT-25 PIT-25EP 100-250° .290" 1Уг» 6 PIT-35 PIT-35EP 200-350° .366" 21/4" 6 PIT-50 PIT-50EP 325-475° .366" 21/4" 6 ♦Differential based on direct bulb Immersion in liquid at 1° per minute rate of change. In a bulb well, differential will widen. When clamped to a surface such as a pipe, differential may be wider or narrower depending on several variables. Electrical Ratings — Table B Voltage, A.C. Only 120 208 240 277 Full Load Amperes 16 9.2 8 — Locked Rotor Amperes 96 55.2 48 — Non-Inductive or Resistance Load Amperes* (Not Lamp Loads) 22 22 22 22 Pilot Duty — 125 VA, 24/600V. A.C. ♦5.P.5.T. Rating Sensitive bulb for PIT and PIT-EP ,_L Depth Incl. Knob 315/16" GENERAL NOTICE; Type PIT controls are designed for temperature control service only. Because they do not fail safe, they should not be used for temperature limiting duty. APPLICATION — Chromalox Type PIT SPDT thermostats are designed for a variety of applications where Rain-tight or Explosion-proof enclosures are necessary or desirable. Typical use is to control the temperature of fluids conveyed through pipes (commonly termed pipe tracing), also used in snow melting applications with electric heating cable. An alarm or signal circuit can be operated by the auxiliary contacts. CAUTION; Ram-Tight models mm not for use in hazardous environments as described in National Electrical Code. Failure to comfiiy can result in explosion or fire. CAUTION: Users should install adequate controls and safety devices with their electric heating equipment. Where consequences of failure may be severe, back-up controls are essential. Although the safety of the installation is the responsibility of the user, Chromalox will be glad to make equipment recommendations. Type PIT — Rain-tight, gasketed enclosure is 0.062 " steel. Simple mounting on 3 rubber-cushioned feet. Has adjustable high limit stop. Plain copper bulb and capillary. Type PIT-EP — Explosion-proof, cast aluminum housing approved for Class I, Group D and Class 6, Groups E, F, G. External adjusting knob. Tin-plated copper bulb and capillary. Can either open or close a circuit on temperature rise. SPDT, snap-acting switch. © 1987 Edwin L. Wiegand Division, Emerson Electric Co. GENERAL {continued) Principle of Operation — Control action of these thermostats is provided through the principle of liquid volume change. With a variation in temperature, the liquid in the sensing bulb expands or contracts, causing a bellows to actuate the switching mechanism. Power Supply — WARNING; Use on AC only. Thermostat is not DC rated. The Rain-tight models only have a keyed adjustable high limit stop. A special wrench is required to adjust this limit stop and is supplied with each control. High Limit Stop Adjustment — The high limit stop can be set at any position between 55 °F. above the lowest dial range and the highest dial range. For example: The high limit stop can be set between 55 °F. and 150 °F. on a thermostat with a range of 0°F. to 150 °F. To change the stop setting,, loosen the .two screws in the dial plate with the wrench packed with the control. Turn the dial so the pointer indicates the stop setting. Move the stop (located behind dial plate) against stop bracket. Tighten screws to lock the stop in position. OPTIONAL ACCESSORY - Bulb Well — Copper bulb wells with lh " NPT brass connectors are supplied when specified. See Specifications for Catalog Numbers. Table C. Bulb Wells - Table С For BuSb Dm Catalog Number "C'‘ Dia. "D" Length .290 CPWC-1 2%" .366 CPWC-2 213io " MOUNTING NOTE: Do not mount control where it will be subject to vibration, shock, grease, or corrosive vapors. Do not mount adjacent to a large magnetic contactor, as vibration and shock will cause thermostat to interact erratically — resulting in chattering of the contactor. The air temperature in and around the control enclosure should be kept as near to normal room temperature as possible.. .never above 150 °F. Indoors, the thermostats may be mounted in any position. RAIN-TIGHT ENCLOSURE TYPE PIT - Outdoors, where exposed directly to weather, the electrical connection and capillary should be on the lower horizontal surface as illustrated in Figure 1. 4 %4" Square % "-14 NPT S* THREADED OUTLET Figure 1 — Interior of Type PIT (3) %/' Dia. Mtg. Holes X Adjustments — The setting may be changed to meet the requirements of th...