Additel 901B - Low Pressure Test Pump

• Generate 6 psi (0.4 bar) vacuum to 6 psi (0.4 bar) pressure
• Adjustment resolution: 0.1 Pa (0.001 mbar), with a screw press designed for fine pressure adjustment
• Isothermal bellows chamber, insulated to reduce the influence of ambient temperature changes
• Specially designed bellows minimize leakage for stable readings
• No check valve (non-returning valve), for minimal maintenance
• Two hand-tight quick connectors: no PTFE tape or wrenches needed
• Portable: only 3.5 lb (1.6 kg)

• Comparison calibration of low pressure gauges, transmitters, and switches up to 6 psi
• Vacuum checks down to 6 psi (0.4 bar) vacuum
• Laboratory low pressure work where stability at each point matters
• Field verification of low pressure instruments with a portable reference setup

• Media: Air
• Generated pressure range: 6 psi (0.4 bar) vacuum to 6 psi (0.4 bar) positive pressure
• Adjustment resolution: 0.1 Pa (0.001 mbar)
• Material: ram/adapters SS; body SS, aluminum; seals Buna-N, PTFE, Copper Alloy
• Connection: hand-tight connectors for both test gauge and reference gauge; 1/4NPT female, 1/2NPT female, 1/4BSP female, 1/2BSP female, or M20X1.5 female
• Dimensions: height 5.7'' (145 mm); base 9.65'' (245 mm) x 6.50'' (165 mm)
• Weight: 3.5 lb (1.6 kg)
• Accessories included: O-rings (20 pcs), manual; carrying case on 901B-X-SET models
• Warranty: 1 year

Low pressure calibration is where hand pumps struggle most. A check valve and a poorly insulated chamber let the reading drift when the room warms up or the operator touches the pump, and at a few psi that drift is a large share of the reading. The Additel 901B is built to avoid both problems.

Its screw press sets pressure from 6 psi (0.4 bar) vacuum to 6 psi (0.4 bar) with an adjustment resolution of 0.1 Pa (0.001 mbar). The isothermal bellows chamber is insulated against ambient temperature changes, and with no check valve there is less to leak and less to maintain. Two hand-tight quick connectors take the test gauge and the reference gauge without PTFE tape or wrenches, and at 3.5 lb (1.6 kg) the pump travels with the technician.

The Additel 102 and Additel 103 fitting kits cover other threads and hand-tight connections. Pair the pump with an Additel 681A digital pressure gauge as the reference.

AV-TEK Consulting supplies Additel pressure calibration equipment across North America and helps you choose the pump and fittings for your instruments. Browse all pressure test and calibration pumps or the full Additel range.