Your Complete Guide to General Electric TPUV8 Replacement Without OEM Delays

The General Electric TPUV8 is a 24VDC undervoltage release (UVR) for GE Power Break I insulated case circuit breakers. It fits the small frame breaker types TRLA, TRLL, TRPA, TRPP, TRL and TRP, rated 800A to 2000A. BRAH Electric makes an aftermarket direct substitute for it, part number BE-TPUV8.

The TPUV8 is a breaker accessory, not the trip unit. The trip unit measures current and trips the breaker on overloads and faults. The undervoltage release watches a control voltage and trips the breaker when that voltage is lost. This guide covers what the part does, the other voltages in the same series, and what to check before ordering.

GE TPUV8 at a glance

• Part type: undervoltage release (UVR), listed under Circuit Breakers, Undervoltage Releases.
• Control voltage: 24VDC.
• Fits: GE Power Break I small frame, types TRLA, TRLL, TRPA, TRPP, TRL and TRP, 800A to 2000A.
• BRAH part number: BE-TPUV8, a direct substitute for GE TPUV8. The GE number is marked obsolete in the BRAH catalogue.
• Same series: nine TPUV releases for the small frame and nine TSUV releases for the large frame, 12VDC through 600VAC.
• Browse all undervoltage releases for circuit breakers.

What an undervoltage release does on a Power Break I breaker

An undervoltage release is a coil-operated device mounted in the breaker. While its coil is supplied with the rated control voltage, the breaker can be closed and will stay closed. When the control voltage drops too far or disappears, the release trips the breaker. A breaker fitted with a UVR will not stay closed until the control voltage is back.

Plants use a UVR where equipment must not restart on its own after a power dip, or where opening a control circuit has to open the breaker. Emergency stop loops and interlock circuits are common examples. Breaking the 24VDC supply to a TPUV8 trips the breaker.

A shunt trip does the opposite job. It trips the breaker when voltage is applied to its coil, and it does nothing when the control supply is dead. Both are coil-operated accessories fitted inside the breaker, so read the part number on the device before ordering. On the Power Break I small frame, the undervoltage releases are TPUV numbers and the shunt trips are TPST numbers.

TPUV and TSUV undervoltage releases BRAH lists for Power Break I

The table lists the 18 BRAH undervoltage releases for GE Power Break I breakers. The BRAH part number is the GE number with BE- in front. TPUV parts are for the small frame and TSUV parts are for the large frame. The number at the end selects the control voltage, and the same number means the same voltage in both groups: 8 is 24VDC on both the TPUV8 and the TSUV8.

The AC releases are listed at 60Hz. Voltages and breaker types are the values in the catalogue record for each part. For anything not in the table, call (855) 355-2724 with the part number.

Signs a TPUV8 needs replacing

A failed undervoltage release usually shows up as a breaker that will not close, or one that trips as soon as it is closed, with no overload or fault present. Before blaming the release, measure the control voltage at its terminals. A blown control fuse, an open interlock contact or a weak 24VDC power supply produces the same symptom, and a new UVR will not fix it.

If the correct voltage is present at the coil and the breaker still will not latch, the release is the likely cause. Typical faults are an open or burnt coil, a damaged lead, or a mechanism that sticks. A coil that has been fed the wrong voltage often shows heat damage. Replace the release with one of the same voltage and the same frame group.

Before you order: what to check

• The number on the installed part. Confirm it reads TPUV8. A TPUV7 is 12VDC and a TPUV9 is 48VDC, and they are easy to misread on an old label.
• Control voltage, and AC or DC. Measure the supply that feeds the release. The TPUV8 is a DC part. The 120VAC part for the same breakers is the TPUV1.
• Breaker frame. Read the breaker type from the breaker nameplate. Types TRLA, TRLL, TRPA, TRPP, TRL and TRP take TPUV parts. Types TPS, THS, TPSS and THSS take TSUV parts.
• UVR or shunt trip. Check which device the control scheme calls for. They are separate parts and do opposite jobs.
• The control circuit. If the old coil burnt out, find out why before fitting the new one. Check the supply voltage and the wiring to the release.

BRAH Electric designs its parts in-house and tests them at its Carlsbad, California facility. It is an aftermarket manufacturer and is not an authorized General Electric distributor. Undervoltage releases carry a 2-year warranty from the date of invoice. In-stock orders placed before 3:00 PM Pacific ship the same business day. For help confirming a part, call (855) 355-2724, Monday to Friday, 6AM to 5PM Pacific.

Other BRAH parts for the same Power Break I breakers

A Power Break I breaker that is mechanically sound can often be kept in service by replacing the accessory that failed. BRAH lists these parts for the same breakers:

• Shunt trips: TPST parts for the small frame and TSST parts for the large frame, in 12VDC, 24VDC, 48VDC, 125VDC, 250VDC, 120/240VAC and 480/600VAC. The 24VDC small frame shunt trip is the BE-TPST8.
• Rating plugs for Power Break I breakers with MicroVersaTrip trip units.
• Face plates: replacement nameplates for small frame and large frame Power Break I breakers.

For a wider view of which breaker parts can be replaced on their own, see the guide to circuit breaker replacement parts.

Safety when working on breaker accessories

Fitting an undervoltage release means working inside the breaker. De-energize the breaker and the control circuit, apply lockout/tagout to both sources, and verify the absence of voltage before removing covers. Follow the breaker manufacturer’s instructions for any stored-energy mechanism. The work should be done by qualified personnel, and the breaker should be function-tested before it goes back into service: confirm that it closes with control voltage present and trips when the voltage is removed.

GE TPUV8 replacement FAQs

Is the TPUV8 a trip unit?

No. The TPUV8 is an undervoltage release. It trips the breaker when its 24VDC control supply is lost. Overload and short-circuit protection come from the breaker’s trip unit, which is a separate part.

What voltage is the TPUV8?

24VDC. The other parts in the TPUV series cover 12VDC, 48VDC, 125VDC, 250VDC, 120VAC, 240VAC, 480VAC and 600VAC.

Which breakers does the TPUV8 fit?

GE Power Break I insulated case breakers in the small frame, types TRLA, TRLL, TRPA, TRPP, TRL and TRP, rated 800A to 2000A.

What is the difference between a TPUV8 and a TSUV8?

Both are 24VDC undervoltage releases. The TPUV8 is for the small frame Power Break I, 800A to 2000A. The TSUV8 is for the large frame types TPS, THS, TPSS and THSS, 2500A to 4000A.

Can I fit a TPUV release with a different voltage?

Only if the control circuit supplies that voltage. The release must match the control supply in both voltage and type, AC or DC. Changing the release without changing the supply will either keep the breaker from closing or damage the coil.

What is the BRAH part number for the TPUV8?

BE-TPUV8. Every release in the table follows the same rule: the GE number with BE- in front.

References

• UL 489, Molded-Case Circuit Breakers, Molded-Case Switches and Circuit-Breaker Enclosures. The UL standard that covers molded-case circuit breakers.
• OSHA 29 CFR 1910.147, The control of hazardous energy (lockout/tagout).
• NFPA 70E, Standard for Electrical Safety in the Workplace.