ZINSCO QCAL-70D U 70A 240V 3-pole Molded Case Circuit Breaker DELTA QCAL70D

Description:

The Zinsco QCAL-70D U is a 70 Amp, 3-pole molded case circuit breaker designed for use in Zinsco / GTE Sylvania panelboards. It operates on 240V systems and features a thermal-magnetic trip mechanism that protects circuits from overloads and short circuits. It belongs to the QCAL (QC/QCAL series) and uses a plug-in (snap-in) mounting style for installation in compatible panels. This specific model is configured for delta systems (“D” designation), supporting three-phase power distribution. Listings confirm its rating as 70A, 240V, 3-pole delta configuration.

Applications:

The Zinsco QCAL-70D breaker is commonly used in commercial and industrial electrical systems requiring 70A three-phase protection, particularly in delta-configured systems. Typical applications include motor control panels, machinery, pumps, compressors, and distribution feeders. It is intended for legacy Zinsco panels and is primarily used today for maintenance or replacement of existing installations rather than new installations.

Technical Specifications:

• Manufacturer: Zinsco / GTE Sylvania
• Model / Part Number: QCAL-70D U
• Product Type: Molded Case Circuit Breaker
• Poles: 3-Pole
• Current Rating: 70 Amps
• Voltage Rating: 240 VAC
• Mounting: Plug-in / Snap-in (QC/QCAL series)
• Trip Type: Thermal-magnetic
• Phase: 3-phase (Delta configuration)
• Interrupt Rating: ~10 kAIC @ 240V (typical class)
• Function: Overcurrent and short circuit protection
• Status: Obsolete / discontinued (surplus availability)

Common Replacements:

• Square D QOB370 3-Pole 70A Bolt-On Circuit Breaker
• Siemens BQD370 3-Pole 70A Bolt-On Breaker
• Eaton BAB3070H 3-Pole 70A Bolt-On Breaker