Square D PGA36120YP PowerPact P MCCB Unit

Module Feature

PGA36120YP is a PowerPact P-frame molded case circuit breaker manufactured by Square D. It adopts I-Line plug-in line side connection, load side fitted with terminal lugs. Equipped with ET1.0I basic electronic trip unit, provides instantaneous short-circuit protection. Frame rating 1200A, 3-pole, rated voltage 600VAC. The YP suffix indicates standard handle with padlock provision for lock-off safety. Auxiliary contact, alarm switch and shunt trip accessories are field installable. Widely stocked as spare for commercial building, factory low voltage I-Line distribution panel.

Working principle

Built-in current transformers sample three-phase current and feed signal to ET1.0I trip unit. When short-circuit current exceeds instantaneous threshold, the trip unit triggers rapid contact separation and arc extinguishing. This basic ET1.0I version only supports instantaneous short-circuit protection, without adjustable overload long delay and short-time delay function. Auxiliary contacts output ON/OFF and trip dry contact signals for remote status monitoring.

Onboard componentsCurrent transformer group, ET1.0I electronic trip unit, main contact assembly, arc quenching chamber, spring operating mechanism, I-Line plug connector, load terminal lugs, padlockable operation handle and reinforced insulated housing.

LED indicatorsFront mechanical markers show ON, OFF and tripped status.

Hardware self‑diagnosisTrip unit monitors CT signal and internal power supply. Instantaneous trip threshold is fixed according to factory setting.

Programming softwareNot applicable for ET1.0I basic trip version.

Electrical & Process Parameters

Model: PGA36120YP Brand: Square D (Schneider Electric) Device type: Molded case circuit breaker Frame rating: 1200 A Pole: 3P Rated voltage: 600 VAC Icu: 18 kA @600VAC Trip unit: ET1.0I (instantaneous only) Mounting: I-Line plug-in Function: Instantaneous short-circuit protection for low voltage distribution feeders

Mechanical & Structure

Mounting: I-Line plug-in mounting inside LV switchgear Protection class: IP40 front panel Housing: Reinforced insulated plastic enclosure

Environmental

Operating temperature: -25℃ ~ +60℃ Storage temperature: -40℃ ~ +85℃ Ambient humidity: 5~95% non‑condensing

Certification: UL489, CSA, CE Status: Original Square D electrical distribution spare

Installation

Cut off upstream power supply before replacement. Align breaker with I-Line bus and lock into connected position, tighten load side lug bolts, wire auxiliary or trip accessories if fitted, test close, open and instantaneous short trip function after commissioning.

Interface

I-Line plug-in line terminals, load side lug terminals, auxiliary/alarm contact terminals, shunt trip terminals.

Diagnostic

Instantaneous trip: Severe short circuit on downstream circuit. Failed closing: Mechanism latch stuck or handle not reset from trip position. No trip action: Trip unit damaged or CT circuit open.

Product Brief

PGA36120YP breaker, Square D PowerPact P 3P 1200A I-Line plug-in MCCB spare for low voltage I-Line panel feeder short-circuit protection replacement.