Marsh Bellofram PCD Division Type 1500 I/P and E/P Transducers - Marsh Bellofram - #1

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www.marshbellofram.com • 800.727.5646 67 Transducers Type 1500 Description The T-1500 is a new series of electro-pneumatic transducers that convert an electrical signal to a proportional pressure output. It provides precision electro-pneumatic control to actuators, valves, positioners, final control elements and is ideally used for high-flow control devices. The Type 1500's compact size and accessibility to ports and adjustments allow the unit to be installed in space-constrained locations or in a manifold for multi-device control. DIN rail and manifold assemblies are available in kits that provide three, five or ten mounting points. An integral pneumatic volume booster is included in the Type 1500 design to provide high flow capacity. (See specifications for flow data.) Standard Features • Small footprint, compact size • Manifold mounting configurations • Built-in volume booster • Electrical Connections: Conduit 12 NPT or BSPT, Terminal Block, Hirschmann® Connectors (DIN 43 650-A) • Supply and output ports on front and back of unit • Low air consumption • External zero and span adjustments • Low cost • Field accessible orifice • Electrical conduit connection meets CE requirements Options Available • Intrinsically Safe (FM, CSA, ATEX) • NEMA 4X (FM, CSA) Excludes Terminal Block Applications The T-1500 transducer can be used as an electro-pneumatic control device to operate: • Valve actuators • Valve positioners • HVAC systems • Material handling systems • Paper handling controls • Automation systems • Liquid and gas processing systems Type 1500 I/P & E/P Transducers Principle of Operation (See Fig. 2 and 6) The T-1500 Transducer is a force balance device in which a coil is suspended in the field of a magnet by a flexure. Current flowing through the coil generates axial movement of the coil and flexure. The flexure moves against the end of a nozzle and creates a back pressure in the nozzle by restricting air flow. This back pressure acts as a pilot pressure to an integral booster relay. Consequently, as the input signal increases (or decreases for reverse acting), output pressure increases proportionally. In the zero based T-1500, the output of the transducer section is routed to an integral negative bias booster relay. The bias relay allows the complete unit to regulate output pressure down to 0 psig/BAR. The bias relay also amplifies the output of the transducer which allows the zero based units to regulate higher output pressures than the standard T-1500. Zero and Span are calibrated by turning easily accessible adjusting screws on the front face of the unit (see Figures 3, 4, 5, 7, 8 and 9). The zero adjustment causes the nozzle to move relative to the flexure. The span adjustment is a potentiometer that limits the flow of current through the coil. A thermistor circuit in series with the coil provides temperature compensation. Mounting The T-1500 can be mounted at any angle but should be calibrated after mounting. For maximum output pressure stability, the T-1500 should be mounted vertically in a vibration free location or such that the vibration is isolated to the X and Z axis. The T-1500 can be in-line, panel, pipe, DIN rail or manifold mounted. Air Connections 1. Supply Air must be instrument quality air regulated between 5 PSI above maximum output pressure up to 120 PSIG / 8.3 BAR (See table: Supply Pressure Range). 2. Instrument-quality air consists of: a. A dew point less than 35¢ªF b. No particles larger than three microns c. Maximum oil content of 1 ppm 3. All unused ports must be plugged. Type 1500 Transducers Supply Connect supply to either of two ports marked “IN” on the base of the transducer. Avoid getting pipe sealant inside the piping or transducer. Output Connect output to either of two ports marked “OUT” on the base of the transducer. The second “OUT” port may be used for a pressure gauge.