Section 5—PowerPacT P-Frame Molded Case Circuit Breakers

P-Frame Unit-Mount

P-Frame I-Line

P-Frame Drawout

Providing unparalleled performance and control, the P-frame circuit breakers features the exclusive MicroLogic electronic trip units, which allow for a range of sophisticated applications for metering and monitoring. In addition, trip units can be interchanged in the field to allow for maximum flexibility.

The compact size and small footprint of the P-frame circuit breaker permits high density installations in I-Line panelboards and switchboards. These circuit breakers are available in 100% rated construction for all unit-mount circuit breakers and up to 800 A in I-Line circuit breakers to meet a broad range of commercial and industrial application needs.

• Both standard (80%) and 100% rated construction circuit breakers are available in 1200 A with a sensor size range of 250–1200 A.

• Interrupting ratings (AIR):

• The P-frame circuit breakers with K interrupting rating are recommended for applications having high inrush and/or non-linear loads such as large motors, transformers, motors with soft starts, etc.

• ComPacT circuit breaker size allows for small footprint installations using I-Line panelboards and switchboards. Nine inch width provides increased density installation.

• Most field-installable accessories are common to all frame sizes for easier stocking and installation

• Selection of four interchangeable MicroLogic trip units available, with PoweLogic power metering and monitoring capabilities available in advanced trip units.

• Field-installable sensor plugs. See Sensor Plugs.

• Compatible with PowerLogic systems and high amperage power circuit breakers.

• Built-in Modbus protocol provides an open communications platform and eliminates the need to purchase additional, proprietary network solutions.

• Connection options include bus, cable or I-Line for installation flexibility.

• Additional options are available for 5-cycle closing, stored energy mechanisms and drawout-mounting.

All circuit breakers marked as 100% rated can be continuously loaded to 100% of their rating.

Because of additional heat generated when applying circuit breakers at 100% of continuous current rating, the use of specially-designed enclosures and 194°F (90°C) wire is required. The 194°F (90°C) wire must be sized according to the ampacity of the 167°F (75°C) wire column in the NEC. Minimum enclosure size and ventilation specifications are indicated on the circuit breaker, in its instruction bulletin, and in Enclosure Sizes.

Circuit breakers with 100% rating can also be used in applications requiring only 80% continuous loading.

Automatic molded case switches are available in individually-mounted and I-Line constructions from 600–1200 A. Automatic switches are similar in construction to electronic trip circuit breakers except that long-time tripping is not present. The switches open instantaneously at a non-adjustable magnetic trip point calibrated to protect only the molded case switch itself. They must be used in conjunction with a circuit breaker or fuse of equivalent rating.

Motor circuit protectors Catalog numbers for motor circuit protectors are designated by M68, M69, or M70 in positions 11–14 (trip system). See the table below.* are similar in construction to thermal-magnetic circuit breakers, but have only instantaneous trip functions provided by the ET1.0M trip unit. These motor circuit protectors comply with NEC requirements for providing short-circuit protection when installed as part of a listed combination controller having motor overload protection. Interrupting ratings are determined by testing the motor circuit protector in combination with a contactor and overload relay.

Motor circuit protectors are available in PJ and PL individually-mounted and I-Line construction. According to the NEC, the instantaneous trip of the motor circuit protector may be set to a maximum of 8 to 17 times motor Full Load Amps (FLA), but a setting as close as possible to inrush current (without nuisance tripping) results in the best protection. The instantaneous trip pickup level is adjustable within the ranges shown below.

Select motor circuit protectors as follows:

1. Determine motor horsepower (hp) rating from the motor nameplate. The selection table is suitable for motors with locked-rotor indicating code letters per NEC Table 430-7 (b) as follows:

   	Horsepower	Motor Code Letters
   	30–150	A–G
   	150 or More	A–F

   NOTE: For other motors contact Schneider Electric.

2. Select a motor circuit protector with an ampere rating recommended for the hp and voltage involved.

3. Select an adjustable trip setting of at least 800% but not to exceed 1300% (1700% for high-efficiency motors) of the motor full load amperes (FLA).

4. The NEC 1300% maximum setting (1700% for high-efficiency motors) may be inadequate for motor circuit protectors to withstand current surges typical of the magnetization current of auto-transformer type reduced voltage starters or open transition wye-delta starters during transfer from “start” to “run,” constant hp multi-speed motors and motors labeled “high efficiency.”

5. Part-winding motors, per NEC 430-3, should have two motor circuit protectors selected from the above at not more than one-half the allowable trip setting for the horsepower rating. The two circuit protectors should operate simultaneously as a disconnecting means per NEC 430-103.

Electrically-operated P-frame circuit breakers are available in I-Line and unit-mount construction up to 1200 A and are denoted in the catalog number by an “M_” suffix. These come equipped with a two-step stored energy mechanism and come standard with a motor assembly. These are available factory-installed only.

Motor assemblies provide on and off control from remote locations. The assemblies contain a spring-charging motor (MCH), a shunt trip (MX) and a shunt close (XF) and are available in standard or communicating versions. An SDE overcurrent trip switch is also included for trip indication. When remote indication of the circuit breaker status is required, use of a circuit breaker with an OF auxiliary switch for on-off indication. See Indication Contacts for details.

Unit-mount circuit breakers and switches have mechanical lugs standard on both ends. I-Line circuit breakers have lugs standard on the O/OFF end. These lugs accept aluminum or copper wire. Manually-operated P-frame circuit breakers are also available in drawout construction. See Mechanical, Compression, and Distribution Lugs for more lug options.

Control wiring for unit-mount and I-Line construction is connected to terminals located under the circuit breaker accessory cover. Control wiring for drawout construction is connected to terminals located on the cradle.