Type PMI, 38-72.

5 kV, up to 40 kA
Power Circuit Breaker

Standard features
- Dead tank design, with one self-blast interrupter per tank on a
galvanized steel frame
- All tanks factory leak tested in a hard-vacuum chamber with a
helium mass spectrometer
- Certified per ANSI C37.04, C37.06, and C37.09 Standards
- Three maintenance-free HMB-1 spring-hydraulic mechanisms
- Frame mounted NEMA-3R steel control cabinet protected with TGIC
polyester powdercoat finish
- Single tank-mounted gas density monitor and pressure gauge
- Porcelain bushings
- Continuous current ratings through 3000 A
- Ships fully assembled and factory tested with 5 psig SF6 gas

Options and accessories

- Switching Control Sentinel (SCS) for reduction of switching
transients
- Condition monitoring with the Circuit Breaker Sentinel (CBS)
- Density monitor and temperature-compensated pressure gauge
directly-mounted on each tank
- Extra creep and/or extra strike bushings for special applications
- Silicone rubber composite bushings
- Tank heaters for operation in ambient temperatures below -40C
- High seismic designs
- National Board certification of interrupter tanks per the ASME
Pressure Vessel and Boiler Code

With a large installed base and proven track record, the PMI
breaker offers unequalled performance and reliability.

Independent Pole Operation Conventional gang-operated circuit

(IPO) mechanism and power breakers switch their loads randomly
quality improvement through with respect to the bus voltage. That
controlled switching can severely degrade power quality
Three type HMB-1 spring- due to the resulting generation of
hydraulic mechanisms are potentially damaging voltage and
located within the 72PMI current transients. Maximum voltage
breaker control cabinet. Each transients occur, for example, when a
mechanism drives a separate capacitor bank is energized at a bus
interrupter to provide voltage peak.
independent pole operation. A
stack of disk springs within each unit stores mechanical energy. That Adding the optional Switching Control
energy is hydraulically translated through an operating shaft to open Sentinel (SCS) enables a 72PMI
and close the contacts of its respective interrupter. Spring charge is breaker to reduce the severity of such transients by controlling each
automatically maintained by a universal motor and pump. Each fully phase to close near a respective voltage zero crossing, which
integrated mechanism is self lubricating and hermetically sealed, dramatically improves system power quality.
affording excellent reliability and long term stability.
 89 7/8" (2284)
SHIPPING AND INSTALLED WIDTH

33 5/8" (855) 33 5/8" (855)

PHASE SPACING PHASE SPACING 36" (918.4)

27" (688) 27" (688) 12" (305) 66 7/8" (1698) 29 1/2"

METAL TO METAL METAL TO METAL ADDITIONAL HEIGHT REQUIRED CLEARANCE TO REMOVE INTERRUPTER (749)
FOR BUSHING REMOVAL METAL TO METAL

19 5/16"
(491)
MIN. METAL
TO GRD.
133 5/16"
(3386)
INSTALLED
HEIGHT

101 7/16" 130 5/16"

Document Number - 2GNM110053 / January 2009

(2576) (3310)
SHIPPING INSTALLED
HEIGHT HEIGHT
80 60
100 PSIG

RUPTURE
40

120
20

140

DENSITY MONITOR

TO TOP OF DISC
BUSHING

128"
(3251)
LIVE
PARTS

109" 63 3/32"
(2770) (2365) 145 1/2"
MINIMUM
HEIGHT TO (3696)
BUSHING
BREAKER C/L
HEIGHT

32 3/8"
31 7/8" (822) 70 3/16"
(810) BOTTOM (1782)
OF HEIGHT OF
LEG
CONTROL COUNTER
EXTENSIONS
CABINET

Rated capabilities
Short Circuit Maximum Power Frequency 2 -sec Chopped
Rated Maximum and Short Time Continuous Rated Interrupting Full Wave Insulation Wave Impulse Closing and
Circuit Breaker Voltage Current Current Time Withstand Voltage Withstand Voltage Voltage Latching Current
Type (kV, rms) (kA, rms) (A, rms) (Cycles) (kV, Peak) (kV, rms) (kV, Peak) (kA, Peak)

38PMI31-12 38 31.5 1200 3 200 80 258 82

38PMI31-20 38 31.5 2000 3 200 80 258 82

38PMI31-30 38 31.5 3000 3 200 80 258 82

38PMI40-12 38 40 1200 5 200 80 258 104

38PMI40-20 38 40 2000 5 200 80 258 104

38PMI40-30 38 40 3000 5 200 80 258 104

48PMI31-12 48.3 31.5 1200 3 250 105 322 82

48PMI31-20 48.3 31.5 2000 3 250 105 322 82

48PMI31-30 48.3 31.5 3000 3 250 105 322 82

48PMI40-12 48.3 40 1200 5 250 105 322 104

48PMI40-20 48.3 40 2000 5 250 105 322 104

48PMI40-30 48.3 40 3000 5 250 105 322 104

72PMI31-12 72.5 31.5 1200 3 350 160 452 82

72PMI31-20 72.5 31.5 2000 3 350 160 452 82

72PMI31-30 72.5 31.5 3000 3 350 160 452 82

72PMI40-12 72.5 40 1200 5 350 160 452 104

72PMI40-20 72.5 40 2000 5 350 160 452 104

72PMI40-30 72.5 40 3000 5 350 160 452 104

For more information please contact:

ABB Inc.
High Voltage Products
Westmoreland Distribution Park East
100 Distribution Circle
Mount Pleasant, Pennsylvania, USA
Phone: +1 (724) 696-1500
Fax: +1 (724) 696-1502

www.abb.com/highvoltage