Gestra TA7

BRAND : Gestra

Description

Electronic unit for the generation of periodic pulses to initiate a blowdown cycle via the GESTRA rapid-action intermittent blowdown valve type MPA 46 or 47, i.e. automation of intermittent boiler blowdown. Equipment for steam boilers to TRD 401, section 6.4. The programme-controlled blowdown system consists of an electronic cycling timer, a three-way solenoid valve and a strainer. The equipment meets the German regulations for use in steam-boiler plants operating without constant supervision or with limited supervision (TRD 602 and TRD 604, sheet 1).

Function

The cycling timer type PRS 8 generates a control pulse which, after the preset blowdown interval, operates the three-way solenoid valve. This in turn actuates the rapid-action blowdown valve by means of compressed air or pressurized water and closes it again at the end of the pulse (blowdown) duration. The blowdown interval and the pulse duration can be coarsely preset with a code switch. Final adjustment is carried out with the aid of two potentiometers. For test purposes and in the event of power failure the three-way solenoid valve can be operated by hand. A push-button manual override is provided on the solenoid valve which allows a test of the blowdown valve as required by certain regulations in force.