Condor · MDR 3
MDR 3
The reason Condor shows up on three-phase machines: MDR 3 builds switch all three motor poles directly and can be ordered with an integrated adjustable thermal overload, so a small three-phase recip needs no separate starter.
Specifications
- Action
- Standard — contacts open on rising pressure
- Adjustable range
- Selected by build; common industrial compressor ranges
- Differential
- Adjustable hysteresis (adjustable)
- Factory settings
- Per OEM build
- Ports
- Metric G 1/4 typical
- Unloader
- Optional integrated unloader
- Lever / disconnect
- Integral rotary handle
- Enclosure
- Sealed industrial housing
- Temperature
- Per datasheet
Electrical
- Three-phase, 400 V class construction
- Optional integrated thermal overload relay with adjustable trip current — set it to motor FLA
- Integral on/off handle switching all poles
Size against motor full-load amps with the motor amperage calculator, and check feeder sizing with the voltage drop calculator.
Adjustment
- Switching point screw, hysteresis screw, and (if fitted) the overload current dial — three separate settings.
- Set the overload dial to nameplate FLA, not to the breaker size.
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
- Small three-phase recips up to the switch's rated HP
- Machines where panel space is tight
Watch out
- Above the switch's rated horsepower you must go back to a contactor. Do not oversize by hoping.
- An integrated overload still needs annual verification — check trip current against the motor plate.
Cross-references
- Square D 9013 + separate contactor/overload
- Any IEC starter + pilot-duty pressure switch