Sensor IQ Breaker Handle Ties

General Information -- Why Tie Breaker Handles?

Breaker handle ties mechanically connect the handles of two or more single-pole circuit breakers from which the ungrounded (hot) conductors have been wired to a single grounded (neutral) conductor to create a multiwire branch circuit. Multiwire branch circuits are mostly used to efficiently supply power outlets in a space. For example, the NEC requires a minimum of two small appliance receptacles in a kitchen. Using a multiwire branch circuit to fulfill this requirement allows the electrician to run a single 12/3 cable instead of two 12/2 cables - reducing their time and materials. This same approach can be used for any space requiring power outlets wired to multiple circuits.

Multiwire branch circuits can only be used to supply 120 V normal-only branch circuits and are never allowed for emergency circuits. It is acceptable to have multiwire branch circuits in a panel that is fed by a normal/emergency mains feed as long as none of the connected loads on the multiwire circuit are emergency loads.

Multiwire branch circuits can be connected to either multipole circuit breakers or to multiple single-pole circuit breakers. Both methods are perfectly acceptable, the advantage of using one or the other is a matter of convenience. Let’s go back to our kitchen example: if you use a multipole common-trip breaker to protect both hot conductors and you plug in too many appliances on one circuit, the breaker trip will de-energize both circuits. If you are using two single-pole breakers, then only one will trip, leaving the non-overloaded circuit energized, which may be more convenient.

One of the dangers of using multiwire branch circuits is that all connected hot conductors must be deenergized to safely service devices in an enclosure fed by a multiwire circuit – for example, two duplex outlets in a two-gang backbox. Say you want to replace one of those outlets and your multiwire branch circuit was installed without a 2-pole breaker or a handle tie. When you flip the handle to disconnect the breaker wired to the hot conductor feeding the outlet you want to replace, the other hot conductor in the backbox is still energized. Breaker handle ties prevent this safety hazard by ensuring that all the conductors of the multiwire branch circuit are deenergized whenever any of them are disconnected.

As a result, NEC 210.4(B) requires that:

Each multiwire branch circuit shall be provided with a means that will simultaneously disconnect all ungrounded conductors at the point where the branch circuit originates.

And NEC 2403.15(B)(1) states that:

Individual single-pole circuit breakers, with identified handle ties, shall be permitted as the protection for each ungrounded conductor of multiwire branch circuits that serve only single-phase line-to-neutral loads.

The NEC defines “disconnect” and “protection” separately. Disconnect refers to a manual operation such as flipping a breaker handle. Protection is an automatic operation such as a breaker trip. This distinction is why NEC 240.15(B)(1) does not contradict NEC 210.4(B).

ETC Application

Since ETC does not serve the residential market, you may be wondering how any of this applies to our products. Energy codes applying to our markets mean we need to support multiwire branch circuits. ANSI/ASHRAE/IES 90.1, CEC Title 24, and IECC C405.11 all require the use of controlled power receptacles in offices, hotels, and other spaces under their purview. The requirement for “plug load control”, as it is often called, reduces power consumption by automatically shutting off power to receptacles when a space is vacant for a specified amount of time or by scheduled building sweeps at the end of the day. Sensor IQ enclosures paired with ETC lighting control systems meet the requirements for plug load control.

The same advantages to using multiwire branch circuits to supply outlets on a kitchen countertop apply to wiring outlets anywhere else. When you put that in the context of wiring a large open work area, the benefit of using three wires to do the work of four – or better yet, using four wires to do the work of six – adds up considerably. Sensor IQ Breaker Handle Ties allow electrical contractors to wire up controlled outlets safely and efficiently.

Echo/Elaho Relay Panel Mains Feed (ERP) and Echo/Elaho Relay Panel Feedthrough (ERP-FT) can also be used for plug load control on multiwire branch circuits. ETC does not supply breaker handle ties for these enclosures because a) we use an off-the-shelf Siemens breaker panel in ERP enclosures allowing contractors to easily source breaker handle ties from their usual electrical supplier, and b) we do not provide any of the circuit breakers or panels supplying branch circuits to ERP-FT enclosures.

Product Details

ETC part number CB1065 – SNSR IQ BREAKER HANDLE TIE KIT 2P/3P

• Model number IQ-TIE
• In stock as of May 2024
• Replaces CB1064 – 2-pole handle tie kit
• While CB1064 is discontinued, any CB1064 already in the field can be installed without concern
• Includes 2 screws, spacers, nut, breaker labels, and instruction guide in a plastic bag
• Kits are built by Carling, the manufacturer of Sensor IQ breakers

CB1065, as shipped from ETC

Installation Notes

The labels included in the kit must be applied to all breakers connected by the handle tie. The labels are designed to be applied to the area indicated below:

Once installed, IQ breaker handle ties will not interfere with the handle operation of breakers that do not have handle ties installed. However, as you can see in the photo below, handle ties can interfere with the handle operation of breakers that do have handle ties installed. Here are the best practices for avoiding this issue in IQ enclosures that are supplying more than one multiwire branch circuit:

Group the sets of breakers supplying multiwire branch circuits such that no set is directly above or below another set. Grouping sets of breakers side by side, or with a single, non-tied breaker between them is not an issue. If you cannot avoid having two sets of tied breakers installed vertically next to each other, make sure the screws are oriented the same way.  As you can see in the photo, the interference is caused by the threaded end of the screws poking out further from the handle than the screw head. If both screws in this photo were oriented with the head at the top, there would be no issue.

What to Expect in the Field

The images below were taken in the Power Lab and show two different sets of three single-pole Sensor IQ breakers with their handles tied together. The orange spacers and stickers fulfill the NEC requirements for clearly indicating handle ties. We intentionally shorted one circuit breaker out of each set to observe the effect of an internal trip on the connected breaker handles. As you can see, the handles of the untripped breakers are holding the handle of the tripped breaker in place.

When you reset the tripped breaker, remember that all of the connected loads on the multiwire circuit will be disconnected as long as the breakers' handle is switched off.

We then metered the output of the tripped breakers. The below images show there is no current on the conductors and the PCP is displaying the expected error messages, despite the physical position of the breaker handle. The overcurrent protection function of Sensor IQ breakers is not affected by the position of the handle.

Code Reference

• NEC 210.4(B) – Requires a means of simultaneous disconnection of all ungrounded conductors in a multiwire branch circuit.

• NEC 240.15(B)(1) – Allows the use of single-pole breakers with handle ties to supply multiwire branch circuits.

• ANSI/ASHRAE/IES 90.1 Section 8.4.2 – At least 50% of all 15 A and 20 A receptacles must run on an automatic control device.

• CEC Title 24 130.5(d) – At least 50% of all receptacles up to 20 A must be controlled.

• IECC 2021 C405.11 – At least 50% of all 15 A and 20 A receptacles must run on an automatic control device.