Zinsco Q243030 Molded Case Circuit Breaker
- 30A
- 3 Pole
- Plug-On
Quantity
Zinsco Q243030 - 30A 3 Pole Molded Case Circuit Breaker
Re-Certified
Quantity
Description
Mounts into legacy Zinsco and GTE Sylvania load centers to provide a seamless replacement for discontinued hardware. The Q243030 is a 3-pole, 30-amp molded case circuit breaker equipped with a green color-coded handle for easy amperage identification. Offering a 10kAIC interrupting rating at 240VAC, this plug-on unit utilizes Magnetrip thermal-magnetic technology to ensure precise protection for commercial environments. It is a direct cross-reference for the UBIZ330 substitute SKU.Specifications
| Brand | Zinsco |
|---|---|
| Part Number | Q243030-R |
| Series | Q |
| Amperage | 30A |
| Poles | 3 |
| Mounting Style | Plug-On |
| Voltage | 240VAC |
| Phase | 3 |
| AIC Rating | 10kA @ 240VAC |
| Terminal Type | Lugs |
|---|---|
| For Use With | Zinsco Load Centers |
| Wire Gauge | 14-8 AWG (Cu/Al) |
| Max Wire | 8 AWG |
| Min Wire | 14 AWG |
| Trip Technology | Thermal Magnetic |
|---|---|
| Trip Function Code | LI |
| Trip Function | Long-Time, Instantaneous |
| Trip Adjustability | Fixed |
| Standards | UL 489 |
|---|---|
| Approval | UL |
| Temp Rating | 40C |
| Construction Features | Magnetrip, Color-Coded Handle (Green) |
Product FAQs
6 answersWhich load centers are compatible with the Q243030 circuit breaker?
This breaker is designed specifically for use in legacy Zinsco and GTE Sylvania load centers that accept Q-series plug-on breakers.
What is the modern cross-reference for the legacy Zinsco Q243030?
The Connecticut Electric UBIZ330 is a direct substitute and modern replacement for the legacy Zinsco Q243030 circuit breaker.
What wire sizes and conductor materials are supported by the Q243030 terminals?
The lug terminals accept wire gauges from 14 AWG to 8 AWG and are rated for use with both copper and aluminum conductors.
Are there safety concerns associated with legacy Zinsco panels and breakers?
Yes, legacy Zinsco electrical equipment has a documented history of safety issues, including breakers failing to trip during overloads and contacts welding to the bus bar. Electricians often recommend thoroughly inspecting or upgrading these older panels to ensure compliance with modern safety standards.
How does the thermal magnetic trip unit function on the Q243030?
The fixed thermal magnetic mechanism provides dual protection. The thermal element offers long-time delay protection against sustained overloads, while the magnetic element provides instantaneous tripping during short circuits.
How is the Q243030 installed into a load center?
It utilizes a plug-on mounting design, allowing the breaker to snap directly onto the panel bus bar without requiring bolted connections.
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Reviews
Review summary
Customers rate this product 5.0 out of 5 based on 47 reviews.
- CGCrocefissa G.Verified BuyerReviewingSiemens Q115 - 15A 1 Pole Miniature Circuit BreakerI recommend this productRated 5 out of 5 stars9/18/26Quick delivery and great price.
The circuit breakers are at a great cost.
- JBJason B.Verified BuyerReviewingSiemens Q2150B - 150A 2 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars9/18/26Great experience
The product was exactly what I needed and it arrived on time.
- DQDon Q.Verified BuyerReviewingSiemens Q3100 - 100A 3 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars9/14/26Siemens breaker
Great customer experience, great prices and fast shipping... Definitely will be buying her again.
- CSChristopher S.Verified BuyerRated 5 out of 5 stars8/12/26Siemens 60
Perfect new condition
- GSGeorge S.Verified BuyerReviewingSiemens Q2150B - 150A 2 Pole Molded Case Circuit BreakerI recommend this productRated 5 out of 5 stars3/4/26Great service
Every time I call or go online you have the parts I'm looking for.