Dwyer Series 648B and 648C Differential Pressure Transmitters are designed to be used with clean, dry air and other non-corrosive gases. Each unit features a push-activated zero function and an associated LED light indicator. With the convenient push-button, zero calibration can be performed without any additional equipment, which significantly reduces time and cost for users. The dual-colour LED indicates if the transmitter is at normal operation, overpressure, or in the process of zero calibration. The enclosure consists of a flame retardant plastic top cover and a stainless steel bottom plate for ruggedness. The pressure ranges vary from 0.1 in w.c. to 25 in w.c. unidirectional and 0.25 in w.c. to 5 in w.c. bidirectional. Series 648B comes standard with ±0.8% FS* accuracy, while 648C models are available in ±0.4% FS* accuracy for more demanding applications. Wiring time is reduced with the removeable terminal block. Each unit features a 2-wire 4 to 20 mA output that is fully protected against short-circuiting and incorrect wiring.
Service : Air and non-combustible, compatible gases.
Wetted Materials : 302 SS, glass, nickel, silicon rubber, polyethylene, acrylic, ABS and brass.
Accuracy : 648B: ±0.8% FS* at room temperature; 648C: ±0.4% FS* at room temperature. *RSS (Root Sum Square) includes non-linearity, hysteresis and non-repeatability.
Stability : ±1% FS/yr.
Temperature Limits : Operating: 0 to 170°F (-18 to 77°C); Storage: -65 to 185°F (-54 to 85°C).
Pressure Limits : 15 psi (100 kPa) proof pressure; 30 psi (200 kPa) burst pressure.
Thermal Effects : 648B: ±0.025% FS/°F (0.045%/°C); 648C: ±0.020% FS/°F (0.036%/°C).
Power Requirements : 13 to 32 VDC.
Output Signal : 4 to 20 mA.
Zero and Span Adjustments : Push-button for zero, potentiometer for span.
Response Time : Approximately 10 ms.
Max. Loop Resistance : DC: 0 to 950 Ω.
Electrical Connection : Detachable euro-style terminal block.
Process Connections : 3/16″ OD barbed fitting for 1/8″ ID push-on tubing.
Housing : SS and PC+ABS alloy.
Weight : 3.8 oz (108 g).