Siemens ITE BL and BLH Bolt On Circuit Breaker Identification and Replacement Guide

If you’re replacing Siemens BL circuit breakers or Siemens BLH circuit breakers in a lighting panel, start with the complete breaker catalog number and the panel’s identification label. Matching the handle amperage doesn’t mean compatibility. You’ll need the correct pole configuration, voltage rating, interrupting capacity, and mounting.

This guide helps identify ITE bolt-on circuit breakers, and compare BL with BLH to make the right purchasing decision. It also explains why a higher interrupting rating doesn’t make a breaker an approved replacement.

What BL and BLH breakers do

BL and BLH are thermal-magnetic branch circuit breakers for compatible panelboards. Their thermal element responds to overloads, while their magnetic element responds to Siemens ITE BL and BLH short-circuit current. For background on trip technologies, see Relectric’s electronic trip versus thermal magnetic breaker guide.

These lighting panel circuit breakers use a bolt-on connection at the panelboard bus. Keep that mounting arrangement separate from the wire terminals on the load side. A product description that mentions load lugs doesn’t identify how the breaker connects to the bus.

Siemens also offers plug-in breaker families. Relectric’s Siemens QP breaker guide is useful, but a QP breaker isn’t a substitute for a BL or BLH just because the amperage matches.

BL versus BLH interrupting ratings

Siemens identifies BL with a 10 kA interrupting rating and BLH with a 22 kA rating at the applicable listed voltage. Interrupting capacity describes the fault current a breaker can interrupt under its rated conditions. It’s different from the continuous current rating printed on the handle.

For example, B220 and B220H are both 20-amp, two-pole breakers. Their interrupting ratings differ. A 20-amp BLH doesn’t provide a higher normal load allowance than a 20-amp BL. Use the Siemens BL family data sheet to compare the ratings, then verify the specific breaker label.

The panelboard’s overall short-circuit rating is also important. Installing a breaker with a higher individual interrupting rating doesn’t, by itself, increase the rating of the complete assembly. Any series-rated combination must be chosen per OEM documentation.

Identify the breaker and panelboard

Photograph the full catalog number, type designation, amperage, poles, voltage markings, and interrupting rating. Include any suffixes and accessory markings. Relectric’s circuit breaker identification guide can help you organize details before requesting a replacement.

Next, record the panelboard manufacturer, model or interior designation, and label showing allowed breaker types. An ITE name on an existing breaker is a starting point for identification. It doesn’t mean every Siemens-branded breaker will fit or be permitted.

For a Siemens BL breaker replacement, confirm the complete catalog number rather than deciphering only part of it. In B220H, the example identifies a 20-amp, two-pole BLH. Keep additional suffixes intact when contacting your supplier.

BL and BLH catalog number examples

These examples show common selection differences. Product links are provided for sourcing; Siemens documentation and the actual equipment labels support application ratings.

The one-pole examples above are presented for 120 V applications. Don’t interpret a family’s 240 V maximum to mean you can use every one-pole model on any 240 V circuit. Match the exact voltage marking and system configuration. The Siemens miniature breaker selection sheet provides more catalog examples.

Confirm compatibility before ordering

Check the panel’s stated breaker types, mounting interface, available spaces, terminals, and any accessories. Note the required voltage and interrupting ratings. If you’re considering a change from BL to BLH, confirm the panel documentation supports the proposed breaker.

For other legacy Siemens equipment, Relectric’s CED replacement guide shows why replacement decisions depend on the exact Siemens ITE BL and BLH breaker family. CE, CLE, and CED identifiers don’t establish a cross-reference for BL or BLH.

Check the lighting application

If the breaker will switch lighting, verify the required switching-duty marking. Siemens identifies SWD and HID applications within this product family, with separate catalog choices for HID service. Don’t assume that a standard BL or BLH has every lighting-switching qualification.

Likewise, standard BL and BLH breakers don’t automatically supply personnel GFCI or AFCI protection. Where those functions are required, select a device specifically identified for the application and panel. Relectric’s GFCI breaker guide explains that additional protection function; its QPF models are a separate family.

Send your supplier a complete replacement request

Send your electrical parts supplier readable breaker and panel-label photos, the complete catalog number, required quantity, and any accessory details. Know the supply voltage and whether the request is for an exact replacement or an alternative. Include the required interrupting rating or supporting fault-current information when available.

Browse Relectric’s Siemens and ITE circuit breakers, then request a breaker quote with your identification details. Ask to confirm the catalog number, condition, test documentation, and availability. Have qualified personnel perform the installation using the manufacturer’s instructions, including the specified connection torque.

Conclusion

A successful BL or BLH replacement starts with matching the breaker to the documented panel application. Confirm the full catalog number and electrical ratings before ordering. Clear photos and complete panel information answers questions before the replacement reaches your jobsite.