MDR 11 single-phase

European single-phase switch with integral on/off lever

All pressure switches
Condor · MDR 11

MDR 11 single-phase

Condor's MDR 11 is the single-phase pressure switch fitted to most European-built recips. It carries an integral on/off lever, an unloader, and metric G1/4 ports — plan on an adapter for NPT plumbing.

Specifications

Action
Standard — contacts open on rising pressure
Adjustable range
Build dependent, commonly 60–175 psi
Differential
Adjustable on most builds (adjustable)
Factory settings
Typically 116/145 psi (8/10 bar) · 145/175 psi on high builds
Ports
G1/4 metric (1/4 in. NPT adapter needed in North America)
Unloader
Integral unloader standard
Lever / disconnect
Integral on/off lever
Enclosure
IP44 typical
Temperature
-5 °F to 158 °F typical

Electrical

  • Single-phase, up to 16 A depending on build
  • Integral on/off lever switches both poles
  • Some builds include a thermal overload module

Size against motor full-load amps with the motor amperage calculator, and check feeder sizing with the voltage drop calculator.

Adjustment

  1. Range screw sets cut-out; the smaller differential screw sets the gap on adjustable builds.
  2. Settings are marked in bar — convert before you dial (1 bar ≈ 14.5 psi).
Before you open the cover

Kill power at the disconnect and lock out. Bleed the tank to 0 psi. Never set cut-out above the tank data-plate MAWP. Verify your numbers first in the cut-in / cut-out calculator.

Best fit

  • ABAC, Fini, Fiac, Nuair and other European recips
  • Any machine already plumbed metric

Watch out

  • Do not thread NPT straight into a G port — it will seal for a while and then weep.
  • Some MDR 11 builds include the motor overload; a generic replacement without it leaves the motor unprotected.

Cross-references

  • Lefoo LF10 (functional, NPT ports)
  • Square D 9013FHG12J52 with adapters

Manufacturer documents