The plug-on type one-, two-, and three-pole thermal-magnetic circuit breakers from Square D, the QO, QOT, QO-AFI, and QO-GFI, provide overcurrent protection and switching on ac and dc systems. Plug-on QO circuit breakers are intended for use with OEM mounting bases, switchboard distribution panels, NQ and NQOD panelboards, and QO load centers. The HomeLine series, which Square D also offers, cannot be used in place of the QO series.
It contains cutting-edge rapid-release features that increase the effectiveness of the safety and protection it offers.
The QO circuit breakers are frequently employed in commercial buildings for a variety of purposes. Circuit breakers with single, double, and triple poles all have the QO option. These breakers are capable of handling powerful appliances and gadgets.
Its pricing is relatively costly due to its cutting-edge features and quality assurance.
Operating Mechanism of QO Breaker
The toggle mechanism on QO circuit breakers is over-center, trip-free, and features quick-make, quick-break action, as well as positive handle signaling. When a two- or three-pole circuit breaker experiences an overcurrent on any of its poles, all its poles will open at once due to the way that the tripping mechanisms work. A unique thermal-magnetic trip element for each pole has been calibrated for an ambient temperature of 40°C.
A visual cue that the circuit breaker has tripped and cut the circuit is provided by the Visi-trip indication feature found on QO circuit breakers. The red Visi-Trip indicator is visible in a glass in the circuit breaker casing when the circuit breaker has tripped, and the handle returns to its centre position. Only when the circuit breaker has tripped will the Visi-Trip indicator become visible. Trip indicator quickly sets this circuit apart from other circuits that are only on or off. By pushing the handle to the OFF and then the ON positions, the circuit breaker can be reset.
The voltage rating of the circuit breaker must be more than or equal to the system voltage. An overcurrent is cleared by a circuit breaker in two processes. The tripping mechanism is first released once the overcurrent is found by the current measuring system. The contacts split as a result of this. The voltage arc across the connections must then be put out by the circuit breaker. This voltage arc can be effectively put out if the circuit breaker has the right voltage rating. The following voltage systems are approved for use with QO and QOB circuit breakers:
- 208/120 Vac
- 240 Vac
- 120 Vac
- 120/240 Vac
- 48 Vdc
Features of QO Breaker
The features of QO breaker are as follows:
- Lifetime limitation on warranties
- Red indication with Visi-Trip exclusivity.
- Plug-on design; simple installation.
- Mechanism for quick make/quick break.
- Within 1/60th of a second, trigger a reaction.
- The 15 A and 20 A single-pole breakers have a switching duty rating (SWD).
- For switching 120 Vac fluorescent lighting loads, use SWD.
- Breaker for padlocks with a “ON” or “OFF” option.
- Robertson/slot screws are used to terminate wires.
- HACR-type circuit breakers must be used with HACR-type air conditioning, heating, and refrigeration equipment that has motor group combinations.
Avoid Electrical Mishaps with the Installation of QO Breaker
When it comes to acquiring protection from mishaps related to electricity, you would for sure like to choose equipment that will help you the quickest. QO breakers help you by providing security in the quickest way possible. Therefore, when you set out to buy one, make sure that you have done a significant amount of online research. You will find several sellers and it is your job to choose the best in the lot.
Buyers are advised to visit the website of the manufacturers they want to be associated with. There they can find an email id and phone numbers that can be used to reach out to the seller. Once you get the chance to communicate with them, share your requirement, and after you are convinced, you can place your order with the right seller.