SPECBOOK - BULLETIN A3000 SUBMERGIBLE (PRESSURE)(LEVEL) TRANSDUCER

MODEL A3000 D SUBMERGIBLE (GAUGE PRESSURE)(LEVEL) TRANSDUCER

The (level)(pressure) of the __________ shall be sensed by a US Filter Control Systems/Consolidated Electric Bulletin A3000 Submersible Transducer.  The transducer shall be a 4-20 ma DC, two-wire, 15 to 40 VDC loop-powered type with its output signal directly proportional to the measured level excursion over a factory-calibrated range of zero to _____ (feet of water)(PSIG).

MODEL A3000 E SUBMERGIBLE (GAUGE PRESSURE)(LEVEL) TRANSDUCER

The (level)(pressure) of the __________ shall be sensed by a US Filter Control Systems/Consolidated Electric Bulletin A3000 Submergible Transducer.  The Transducer shall be a three-wire type to operate from a supply voltage of 10.5 to 24 VDC and produce a 1-5 VDC instrumentation signal in direct proportion to the measured level excursion over a factory-calibrated range of zero to _____ (feet of water)(PSIG).

MODEL A3000 I SUBMERGIBLE (GAUGE PRESSURE)(LEVEL) TRANSDUCER

The (level)(pressure) of the __________ shall be sensed by a US Filter Control Systems/Consolidated Electric Bulletin A3000 Model 157GSCI Submergible Level Transducer.  The Transducer shall be a four-wire type to operate on 120 VAC incoming power and produce a 4-20 mADC instrumentation signal into a 0-1,000 ohm load in direct proportion to the measured level excursion over a factory-calibrated range of zero to _____ (feet of water)(PSIG).

The transducer/transmitter module shall include: 120 VAC input power transient protection & fusing, a manual mode switch and twenty-turn potentiometer (to simulate the pressure/level signal for test purposes), a 0-1 ma and a 0-1.99 VDC meter drive output, a 4-20 ma DC powered output as well as +12 VDC & +32 VDC regulated outputs.

MODEL A3000 L SUBMERGIBLE (GAUGE PRESSURE)(LEVEL) TRANSDUCER

The (level)(pressure) of the _______ _shall be sensed by a US Filter Control Systems/Consolidated Electric Bulletin A3000 Submergible Transducer.  The transducer shall be a three-wire type to operate from a supply voltage of 10.5 to 24 VDC and produce an instrumentation signal in direct proportion to the measured level excursion over a factory-calibrated range of zero to ________ (feet of water)(PSIG).

BULLETIN A3000- ALL MODELS

A submergible level transducer shall sense the liquid level.  The transducer shall be a (three-wire, loop-powered type with its output signal directly proportional to the measured level excursion over a factory calibrated range.  The Transducer shall be of the solid-state head-pressure sensing type, suitable for continuous submergence and operation and shall be installed in accordance with manufacturer's instructions.

The transducer housing shall be fabricated of type 316 stainless steel and schedule 80 PVC with a bottom mounted diaphragm seal allowing connection to the system pressure tap.

The transducer shall sense water pressure variations and transform these variations directly into a standard process signal of 1-5 VDC over the desired level range (span).  The transducer shall be completely solid state, with no mechanical linkages or moving parts.

The transducer shall incorporate a variable-capacitance transducer element to convert the sensed pressure to a corresponding electrical value.  The sensed media shall exert its pressure against an oil filled Nitrile diaphragm seal having a nickel/chrome plated carbon steel 1/4" NPT connection port (with clean out plug) connected to the transducer's ceramic diaphragm.  The diaphragm flexes minutely so as to vary its proximity to a ceramic substrate to vary the capacitance of an electrical field created between the two surfaces.  A stable, hybrid, operational amplifier assembly shall be incorporated in the transducer to excite and demodulate the sensing mechanism.  The transducer shall incorporate laser-trimmed, temperature compensated, high quality components and construction to provide a precise, reliable, stable output signal directly proportional to the sensed pressure over a factory-calibrated range.

The transducer element shall incorporate high over-pressure protection and be designed to withstand intermittent overpressures five times the full-scale range being sensed.  Metallic diaphragms shall not be acceptable in that they are subject to damage or distortion.  Sensing principles employing LVDTs, resistive or pneumatic elements shall not be acceptable.

The transducer/transmitter shall include easily accessible offset and span adjustments in the upper assembly.  Span shall be adjustable from 100 percent down to 15 percent of the sensor range.  Fine and coarse adjustments for both span and offset shall be provided, using twenty-five turn potentiometers.  Offset and span adjustments shall be non- interactive, for ease of calibration.

The internal pressure of the lower transducer assembly shall be relieved to atmospheric pressure through a heavy-duty urethane jacketed hose/cable assembly and a slack PVC bellows mounted in a vented fiberglass upper assembly.  The sealed breather system shall compensate for variations in barometric pressure and expansion and contraction of air due to temperature changes and altitude as well as prevent fouling from moisture and other corrosive elements.

The transducer assembly shall be installed where directed by the Engineer and connected with other system elements and placed in successful operation.  It shall be provided with input power and output signal transient protection, associated control elements as specified herein and in accordance with manufacturer's instructions.

BULLETIN A3000 OPTIONS

ALL MODELS;  INTRINSICALLY SAFE WIRING BARRIER

Provide an intrinsically safe barrier between the upper and lower assemblies (or ahead of the entire transducer in the case of the A3000 D).  The barrier shall render the level sensing system suitable for use in Class 1, Division 1 Groups A, B, C and D, Class 2, Division 1, Groups E, F and G, and Class 3, Division 1 hazardous locations.

A3000 D & I ONLY;  5-1/2" ANALOG INDICATING METER

Furnish a taut band, +/-2 percent full-scale analog meter with a 4.5" scale arc calibrated in "feet of water" to match the transducer range (or other "engineering units" as required).  Mount on the front hinged door of the upper assembly with a weatherproof clear polycarbonate cover over the meter.

A3000 I ONLY;  DIGITAL INDICATING METER (LED)

Furnish a 3-1/2 digit digital panel meter with a .5" high numeric LED display calibrated in "feet and tenths of a foot", "inches of water" or other engineering units as desired.  The meter shall provide a 0-1999 count range produced by a 1.999 VDC signal.  Lesser values shall be produced by an attenuated signal.  Mount on the front hinged door of the upper assembly with a weatherproof clear polycarbonate cover over the meter.

A3000 D ONLY;  DIGITAL PANEL METER (LCD)

Furnish a 3-1/2 digit digital panel meter with a .5" high numeric LCD display calibrated in "feet and tenths of a foot", "inches of water" or other engineering units as desired.  The meter shall provide a 0-1999 count range produced by a 4-20 ma DC signal.  Lesser values shall be produced by an attenuated signal.  Mount on the front hinged door of the upper assembly with a weatherproof clear polycarbonate cover over the meter.

CONDENSATION-PROTECTIVE HEATER/THERMOSTAT

Furnish a 120 VAC powered resistor heater element and a sealed thermostat to keep the internal temperature of the upper assembly above the dew point to prevent problems associated with condensation.

TCB (TRANSDUCER JUNCTION BOX)

A weatherproof fiberglass junction box shall be provided to terminate the submergible transducer electronics/breather cable.  The junction box shall include a corrosion resistant incoming strain relief connector, breather system PVC bellows and a terminal block.  The installing contractor shall furnish three-wire shielded cable between the junction box and the control panel.