Start with the label you already have.

Quick answer

• Siemens' Murray instructions: "Refer to wiring diagram label on inside of load center door or cover for product ratings, acceptable components" [S10 p.1].
• Siemens' 2019 letter tells owners of pre-2002 Murray products to "refer to the wiring diagram affixed to the inside of the door of the loadcenter for the specific breaker types that are approved for that panel" [S1 p.1].
• Square D's current catalog shows two label samples, a "Box Label Sample" and a "Wiring Diagram Sample", for both QO and Homeline [Q7 p.33, p.34, p.60].

Your panel label

01

Panel catalog number

02

Printed breaker types

03

Date code

Illustrative layout. No real model or rating.

Keep the label and the document together.

Catalog numbers, breaker-type lists and dates are different fields. The actual label can use a different layout.

1. Catalog number

   Record the complete identifier, including suffixes. Square D label samples, pp.33–34, 60

2. Printed breaker types

   Keep the wiring-diagram label with the box label. Murray 4810366, p.1

3. Date code

   Preserve the exact code when comparing an applicable notice. CPSC QO notice

Original drawing and source annotations

The original drawing is schematic, not a product label, field measurement or installation instruction.

Open the original full-size SVG

door of the panel" [C8]

Sources: Q7 = Square D catalog 1100CT0501 (06/2026) pp.33-34, 60 (label and wiring-diagram sample callouts); S10 = Murray/Siemens instructions 4810366 Rev. D pp.1-2; C10, C3, C8 =

CPSC recall notices (1988; 2010; 2022). The panel label and a licensed electrician decide what may be installed.

What the box label shows (Square D samples)

Square D's catalog annotates its QO and Homeline box label samples with these items [Q7 p.33, p.60]:

• "Number of circuits maximum" [Q7 p.33, p.60]
• "Enclosure catalog number" [Q7 p.33, p.60]
• "Catalog number of covers; flush or surface" [Q7 p.33, p.60]
• "See load center interior for the catalog number" [Q7 p.33, p.60]
• "Voltage ratings" and "Amperage rating" [Q7 p.33, p.60]
• "Wire range for lug torque data" (QO sample) and "Wire range for lug torque data table" (Homeline sample) [Q7 p.33, p.60]
• "Short circuit ratings" and "Short circuit ratings and additional or replacement circuit breakers" [Q7 p.33, p.60]
• "UL manifest", "Date code", "Plant code", "Label part number" and "Manufacturer trademark" [Q7 p.33, p.60]

The QO sample also lists "CE if required" and "NOM if required" [Q7 p.33].

What the wiring diagram shows (Square D samples)

The wiring diagram samples carry these callouts [Q7 p.34, p.60]:

• "Square D circuit breakers that may be used in this load center" [Q7 p.34, p.60]
• "Service Equipment marking. Unused neutral branch terminal for equipment grounding, service equipment application only." [Q7 p.34, p.60]
• "Installation of back-fed main circuit breaker and required kit" [Q7 p.34, p.60]
• "Load center accessories" [Q7 p.34, p.60]
• "Alternate wiring diagram for main circuit breaker or main lug" [Q7 p.34, p.60]

On Murray load centers, Siemens' instruction sheet says "Applicable accessories are listed on the wiring diagram label" [S10 p.2].

Reading the catalog number: Square D's own guides

Square D publishes a position-by-position guide for its load center catalog numbers [Q7 p.6, p.46].

Both guides add a note under Position 3: "Number of maximum circuits is specified in the end package label." [Q7 p.6, p.46]

Where recall notices say codes are printed

CPSC notices give label locations for specific products [C2] [C3] [C7] [C8] [C10] [C17]:

• I-T-E (Siemens), 1986–87 load centers. "a five-digit code marked on the top of the wiring diagram label inside the door which is opened to reset the circuit breakers" [C10].
• Siemens and Murray, 2010 [C3]:
  • "The catalog number for the load centers and meter combos is printed on a label inside the metal box door and on the packaging." [C3]
  • For breakers: "'Siemens' or 'Murray,' date codes 0610 or 0710 and the catalog number are printed on a label on the side of the circuit breakers." [C3]
• Square D QO Plug-on-Neutral, 2022 [C8]:
  • "Consumers can find the catalog number and date code on indoor load centers inside the door of the panel." [C8]
  • For outdoor units, "the manufacturing date codes are printed on the inside of the cover or door of the unit or on the box itself when the cover or door is open" [C8].
• Challenger, 1988. "If the name 'Challenger' is embossed on the front of the panel (on the door handle) and/or on the label on the back of the panel/door, that panel may contain circuit breakers requiring replacement." [C2]
• Square D AFCI, 2004. The date codes are "stamped in red on the breaker label located just above the wiring terminal" [C7].
• Eaton meter breakers, 2014. "The catalog number is located on the unit's packaging." [C17]

Brand names as Eaton's classified list prints them

Eaton's list IL00304001Y groups panel catalog numbers under maker headings. On the rendered pages they read [E1 pp.2–3, 5–10]:

• "Square D" [E1]
• "General Electric" [E1]
• "GE" [E1 p.3]
• "Siemens" [E1]
• "Murray" [E1]
• "ITE/Siemens" [E1]
• "Crouse-Hinds/Murray" [E1]
• "Thomas & Betts" [E1]

Our transcription of these pages has 1,539 catalog-number entries, 1,523 of them unique [E1 pp.2–3, 5–10].

Breaker features the makers describe

Compare a printed dimension, not an installation permission. Equal width does not establish a listed or classified combination.

Eaton CH3/4 in. per poleE5 p.5

Eaton BR1 in. per poleE5 p.5

Eaton CL1 in. per poleE12 p.103

Eaton CHQ3/4 in. per poleE5 p.8

Square D QO3/4 in. per poleQ7 p.67

Square D Homeline1 in. per poleQ7 p.67

Siemens QP1 in. per poleS9 p.1

Siemens QD3/4 in. per poleS9 p.47

GE / ABB THQL1 in. per poleG1 p.1

GE / ABB THQP1/2 in. per poleG1 p.1

Original drawing and source annotations

The original drawing is schematic, not a product label, field measurement or installation instruction.

Open the original full-size SVG

"½" THQP"; ABB not accepting new orders as of October 2, 2024

Sources: E5 Eaton Residential Product Guide MZ00400002E p.5, p.8; K5 Eaton KB 000015509; E12 Eaton CA08100002E (2022) p.103; E1 Eaton IL00304001Y p.1; Q6 Square D 0730CT9801 p.3;

Q7 Square D 1100CT0501 pp.45, 67; S9 Siemens SPEEDFAX SF-17 pp.1, 47; S4 Siemens QD brochure p.1; G1 ABB THQP notice (June 28, 2024) p.1. The panel label governs.

Eaton's residential guide compares its two families side by side [E5 p.5]:

• Type CH: "¾-inch wide", "Trips to OFF position", "Sandalwood handle". [E5 p.5]
• Type BR: "1-inch wide", "Trips to CENTER position", "Black handle". [E5 p.5]

Eaton's knowledge article gives the CH handle colour as "tan" [K5].

Square D's catalog compares its two families [Q7 p.67]:

• QO: "QO 3/4 in. breakers feature Visi-Trip trip to center position". [Q7 p.67]
• Homeline: "Homeline 1 in. circuit breakers trip to center position". [Q7 p.67]

Square D describes Visi-Trip this way: "When the circuit breaker has tripped, the handle assumes a center position and the red Visi-Trip indicator appears in a window in the circuit breaker case." [Q6 p.3]

Siemens' catalog headings read "Type QP, 1" Breakers" and "Type QD, 3/4" Breakers" [S9 p.1]. ABB refers to "the standard 1” THQL circuit breakers" and to "½” THQP circuit breakers" [G1 p.1].

Older brand names that appear in the documents

• Eaton: "Eaton has the largest installed base of residential circuit breakers, which includes legacy brands such as Westinghouse, Challenger, Bryant, and our current Type CH & Type BR designs." [E5 p.4]
• Murray: Siemens wrote in 2019 that "The Murray brand of circuit breakers is being phased out and replaced by equivalent Siemens products." [S1 p.1]
• I-T-E: CPSC's 1988 notice describes "I-T-E brand circuit-breaker boxes (load centers)" of "the Circuit Protection Division of Siemens Energy & Automation, Inc." [C10]
• GE: a 2004 CPSC notice names "GE Consumer & Industrial" as a manufacturer of the recalled TSLR1220CSAL meter load center [C13]. ABB's 2024 notice covers THQP and THQL breakers [G1 p.1].

What to bring to an electrician

• The box label and wiring diagram label items listed above [Q7 p.33, p.34, p.60].
• The panel catalog number and the date code [C8] [C10].
• Any Square D statement that applies: Square D says its QO and Homeline load centers "are UL tested, listed, and labeled to accept ONLY Square D circuit breakers" [Q1].
• Any CPSC notice whose identifiers match yours [C3] [C7] [C8] [C10].

Sources

All documents fetched 2026-11-15 or 2026-11-16 and archived with SHA256 (see SOURCE-LIBRARY.csv). Kind: primary = issued by the manufacturer/agency; primary-mirror = manufacturer document hosted by a third party; primary (vendor) = issued by the maker of the replacement product described.

Related reference photographs