TM 5-3895-374-24-2 BULLETIN E-64 SERIES 604 DIFFERENTIAL PRESSURE TRANSMITTER Specifications - Installation and Operating Instructions The  Dwyer  Series  604  differential  pressure  transmitter converts  air  or  compatible  gas  pressure  into  a  standard 4-20 mA output signal for pressure ranges from 0-0.1 up to 0-120" w.c.  Each of the models overlap in range,  so that  any  range  within  these  limits  can  be  achieved  by adjustment  of  the  span  and  zero  controls.    Convenient two-wire   operation   simplifies   installation   and   expands application .,flexibility over three and four wire units. Positive,    negative    or    differential    pressures    can    be measured  within  an  accuracy  of  ±2%  of  span.    The Series  604  transmitter  uses  a  diaphragm  linked  to  a cantilevered  leaf  spring  as  in  the  Dwyer  Magnehelic® gage.    However,  the  mechanical  amplification  achieved by the magnet/ helix/pointer components in the indicating gage   is   eliminated.      Instead   a   silicon   strain   gage   is cemented  to  the  range  spring.    As  this  is  flexed  by applied pressure via the diaphragm, a resistance change is produced which is conditioned and converted into a 4- 20 mA output signal. For  applications  requiring  direct  pressure  or  percent  of full  span  readings,  the  optional  A-701   digital   readout makes an  ideal  companion  device.    It  provides  a  bright .6"  high,  3-1/2  digit,  LED  display  while  also  supplying power to the Series 604 transmitter. For  additional   information   on   these   and   other   Dwyer pressure transmitting instruments, refer to Bulletin E-50. SERIES 604 TRANSMITTER MODELS & RANGES MODEL RANGES IN INCHES OF WATER NUMBER AS STOCKED MIN. RANGE MAX.  RANGE 604-0 0-0.5 0-0.1 0-1.0 6041 0-2.0 0-0.5 0-4.0 604-2 0-10 0-2.0 0-20 604-3 0-50 0-15 0-120 SPECIFICATIONS GENERAL PERFORMANCE AT 70F 4 mA Max. Pressure 50 PSIG surge, 30 PSIG continuous to either pressure connection Zero Output: 20 mA Media Compatibility Air & noncombustible, noncorrosive gases Full Span Output: ±2% Full ELECTRICAL Accuracy (Includes linearity, hysteresis and repeatability.) Span Output Power Supply:    12.3 to 35 VDC Span & ZeroAdjustable to 0.05% Output Signal:    4 to 20 mA D.C ENVIRONMENTAL 20 to 120F (limited at 38 mA) Operating Temperature (dry air) Loop Resistance: 0 to 1135 ohms Thermal Errors: ±1%/50F typical R Lmax+ Vps-12.3V MECHANICAL 6 oz. Warm Up Time: 10 Minutes Weight: Current Consumption 38 mA max. DC Span & ZeroProtected potentiometers. Adjustments: Pressure Connections: Barbed, for 3/16” I.D. Tubing STANDARD ACCESSORIES (2) #10 x 1" Pan head sheet metal screws (page 3-709)