+381 (0)11 21 97 392

HON 638-EP

HON 638-EP is a pilot pd min, pd max with electric/pneumatic loading pressure stage for gas pressure regulators with throttling diaphragm HON 402, HON 502, HON 503 and HON 505 according to DIN EN 334.

HON 638-EP
Honeywell regulators/Pilots for Pilot-Operated Gas Pressure Regulators

The pneumatic pressure control stages monitor the preset limit values. As soon as outlet pressure gets close to these limits during operation, the pneumatic pressure control stages take over and keep the pressure constant. The transition from electronic control to pneumatic control is done automatically and is operated smoothly in both directions.

The following operation modes may be realized between the two pressure limits:

Remote setpoint adjustment: adaptation of setpoints due to frequently changing operating conditions
-integration with process control systems
Flow control, optimising efficient gas supply
-Gas storage in networks and tanks
-meter protection by means of actual flow limitation

Pressure control
-meter protection by means of actual flow limitation according to defined pressure curves throughout a day or week to improve regulating accuracy and stability due to electronic PI or PID control

Features include:
-CE registration according to PED in combination with HON gas pressure regulators
-According to DIN EN 334, the pilot is an integral component of this device
-Maximum admissible pressure PS: 100 bar
-Maximum inlet pressure pu max: up to 100 bar

Pilot HON 638-EP consists of functional modules on a common base plate:
-1st stage: automatic load-limiting stage
-2nd stage: pilot stage controlling the lower outlet pressure limit pd min
-3rd stage: pilot stage controlling the upper outlet pressure limit pd max
-4th stage: electro-pneumatic loading pressure stage converting electric signals into pneumatic signals

All mechanical components of this device are without potential ignition sources and/ or hot faces. They are not subject to ATEX 95 (94/9/EC). All electronic accessories, on the other hand, meet ATEX requirements.


Honeywell announced it has completed its acquisition of the Elster division of Melrose Industries plc, a leading provider of thermal gas solutions for commercial, industrial, and residential heating systems and gas, water, and electricity meters, including smart meters and software and data analytics solutions. Elster also manufactures gas metering and pressure control devices, as well as total solutions for the gas transmission and distribution industry. After the acquisition, Honeywell secured it's position as world's leading company in providing solutions and products in oil & gas industry. According to Fortune ranking, it is one of the 100 largest companies in the world. Immense portfolio, high quality products and competative prices highlight Honeywell above it's competition.

Honeywell Process Solutions (HPS) is a global leader with over 40 years of experience delivering process automation and control solutions that help industrial customers run their operations safely, reliably, efficiently and sustainably through innovative technologies, services and domain expertise. With more than 12,000 employees around the world, HPS serves customers in more than 125 countries in the oil & gas, refining, petrochemicals, pulp & paper, specialty chemicals, pharmaceuticals, industrial power, and mining & minerals industries.

Official web presentationURL dokument