Edwards EH250 HC: 3Ph 380/400 V 50 Hz, IE3 (Europe/China)

Edwards EH250 – Roots pump with hydrokinetic drive

The EH250 belongs to Edwards' EH series of mechanical boosters (250 to 4200 m³/h). It has a pumping capacity of 310 m³/h at 50 Hz and 375 m³/h at 60 Hz and is combined with a suitable backing pump to improve the pumping speed and ultimate pressure of a system. The motor delivers 2.2 kW; the pump weighs 75 kg and is air-cooled.

Hydrokinetic drive

The motor drives one of the rotors via a fluid coupling. At a high gas load the speed of the rotors drops; as the gas load decreases they accelerate to full speed. The pump can thus be operated from atmospheric pressure over the whole vacuum range without overloading the motor – pressure switches, bypass lines or frequency converters are not needed. This limits the differential pressure across the pump, on the EH250 to 0–180 mbar at 50 Hz and 0–150 mbar at 60 Hz.

Typical applications

Edwards names, among others, semiconductor manufacturing, thin-film coating, vacuum impregnation, vacuum distillation, vacuum metallurgy, oil drying and degassing, vacuum packaging, low-density wind tunnels, pharmaceutical freeze drying, steel degassing, space simulation and CO₂ lasers.

Versions of the Edwards EH250

The EH250 is available as an HC version for hydrocarbon oil (oil included) and as a PFPE-prepared FX version (oil separate), each with IE3 motor for 380/400 V 50 Hz (Europe/China), 230/460 V 60 Hz (USA), 200 V 50 Hz and 200/380 V 60 Hz (Asia). The market details come from the Edwards webshop. The standard pumps are not azide-compatible, because cooling coils made of copper that come into contact with the process are fitted.

Advice and service

Ehrler & Beck supports you in selecting the right combination of backing pump and booster, supplies oil and spare parts and carries out maintenance and repair.

Pumping speed 50Hz	310
Pumping speed 60Hz	375
Rated motor power 50Hz	2.2
Rated motor power 60Hz	2.2
Motor efficiency class	IE3
Weight	75
Length	70.5
Width	30.5
Height	27.2
Inlet connection flange	ISO63
Outlet connection flange	ISO40
Noise level	70 dB(A)
Cooling method	Air cooling
Oil type	Ultragrade 20, XTRAGRADE ADVANCED 168

Convert units: Nm³/h to m³/h

Additional technical data