Potter & Brumfield Relays and Circuit Breakers

Potter & Brumfield relays and circuit protection devices for industrial automation, HVAC systems, power control and machine cabinets: selection by series code, coil voltage and load.

Potter & Brumfield T92 series two-pole power relays (up to 50 A)

Heavy-duty two-pole relays engineered for switching compressors, heating elements, HVAC equipment and industrial electric drives. Built for high inrush currents with dielectric strength between contacts and coil up to 4,000 Vrms.

Switching current ratings of 30 A, 40 A and up to 50 A at 277 V AC
Contact configurations in 2 Form A (2 NO) and 2 Form C (2 CO) arrangements
Available in PCB terminal and flange-mount styles with quick-connect tabs
DC coil options from 5 V to 110 V and AC coil options from 12 V to 240 V

Potter & Brumfield T9A series compact PCB and panel relays (up to 30 A)

Single-pole general-purpose power relays in a compact footprint designed for automation boards, power supplies and machine control cabinets. Industry-standard terminal pinout allows direct drop-in replacement.

Rated switching current up to 30 A at 250 V AC operating voltage
Contact arrangements in 1 Form A (NO), 1 Form B (NC) and 1 Form C (CO)
Durable contact materials including silver cadmium oxide and silver tin oxide
Sealed wash-tight enclosures with PCB pins or 6.3 mm quick-connect terminals

Potter & Brumfield SSR and SSRMP solid-state relay modules

Contactless solid-state relays engineered for high-frequency silent switching of heaters, ovens, lighting and electric motors without contact wear. Includes standard industrial hockey pucks and miniature SSRMP units.

Load current ratings from 10 A to 125 A with line voltages up to 660 V AC
Input-to-output optical isolation of 4,000 Vrms protecting control logic
Available in zero-voltage turn-on and instantaneous random turn-on modes
Panel and heat sink mounting options with low thermal dissipation

Potter & Brumfield W58 and W28 thermal circuit breakers

Single-pole thermal circuit breakers designed to safeguard industrial electronics, control enclosures, medical instruments and power units against overcurrent overloads with manual push-to-reset recovery.

Trip current ratings spanning from 0.5 A up to 50 A
Trip-free push-to-reset manual button mechanism for circuit reset
Panel mounting available with threaded bushing or snap-in retainers
Recognized by UL 1077, CSA and VDE standards for harsh environments

Potter & Brumfield KHA, KUP and KRPA industrial plug-in relays

Multi-pole electromagnetic relays housed in clear protective dust covers for socket and PCB mounting. Applied across automation logic, safety interlocks and manufacturing line sequencing circuits.

Contact configurations from 1 to 4 poles (up to 4 Form C double-throw)
Integrated LED status indicators and mechanical position flags
Manual test buttons for quick commissioning and loop verification
Gold-flashed or fine silver contacts for dry-circuit and power switching

Potter & Brumfield CNT and CNS series time delay timing relays

Precision electronic timing relays engineered for cyclic process control, delayed equipment starting, HVAC damper control and conveyor systems with broad timing adjustment ranges.

Timing modes including on-delay, off-delay, interval and cyclical repeat
Wide timing adjustment spans from fractions of a second to multiple hours
Universal coil power inputs 12–240 V AC/DC with standard 8-pin and 11-pin sockets
High repeat accuracy with robust transient voltage and noise suppression

Decoding Potter & Brumfield relay catalog part numbering

Electromechanical relay part numbers from Potter & Brumfield follow a standardized alphanumeric system.

The prefix identifies the foundational series family (such as T92, T9A, KUP or KRPA), while succeeding letter codes denote the housing package and mounting format (P represents printed circuit board pins, whereas S indicates flange mounting with quick-connect tabs or screw terminals).

The central numerical digits specify the contact arrangement (1 Form A, 2 Form A or 2 Form C), followed by contact material codes designating silver cadmium oxide or silver tin oxide metallurgy.

The suffix indicates the coil excitation type and rated voltage (for example, 12VDC, 24VDC, 120VAC or 240VAC).

Matching control coil parameters and switching load requirements

When specifying Potter & Brumfield relays for machine controls, engineers must verify both control coil excitation and contact circuit ratings.

Direct-current coils require adherence to specified pick-up and drop-out voltages, and inductive transient suppression diodes or varistors should be placed across the coil to protect driving electronics.

For alternating-current circuits at 120 V AC or 240 V AC, relays incorporate shading coils on the magnetic pole to suppress mechanical armature hum.

Contact ratings must account for high inrush currents typical of motors, heaters and compressors, ensuring a safety margin of at least 20 to 30 percent over nominal current.

Application guidelines for SSR and SSRMP solid-state relays

Solid-state relays in the Potter & Brumfield SSR and SSRMP series eliminate moving contacts, delivering silent operation and virtually unlimited switching cycles.

Essential engineering parameters include maximum continuous load current, operating AC line voltage, and input control voltage range (typically 3 to 32 V DC or 90 to 280 V AC).

For resistive heating loads, zero-voltage turn-on (Zero Cross) versions minimize high-frequency electromagnetic interference.

When controlling inductive loads like solenoids, actuators or transformers, random turn-on models paired with appropriate RC snubber networks prevent voltage spike re-triggering.

Equipment circuit protection using W58 and W28 thermal breakers

Thermal circuit breakers in the W58 and W28 series provide compact single-pole overload protection for secondary power distribution, control enclosures and instrumentation. The calibrated bimetallic sensing strip trips reliably under sustained current overloads across ratings from 0.5 A to 50 A.

A built-in trip-free mechanism guarantees that the internal contacts remain open during an active electrical fault even if an operator physically holds the reset button down.

Once the overload is resolved and the bimetal cools, circuit operation is restored simply by pressing the push-to-reset button.

Socket mounting, retaining clips and DIN-rail panel hardware

General-purpose plug-in relays such as the KHA, KUP and KRPA families mount into matching industrial sockets designed for DIN-rail or panel fastening. This plug-in construction allows rapid module exchange during routine maintenance without rewiring existing control panel conductors.

To prevent relay displacement in vibrating industrial environments, spring-steel or molded retaining clips secure the relay body firmly within its socket. Compatible sockets offer screw-clamp or push-in spring terminals and accommodate optional LED status indicators and protective diode modules.

Preparing technical inquiries for Potter & Brumfield components

To ensure quick and accurate quotation, supply the complete part number stamped on the relay case (such as T92P7D22-24, T9AP1D52-12, SSR-240D25 or W58-XB1A4A-15) or provide clear photographs of the component marking plate.

If the part number is worn, specify the mounting footprint, coil voltage, contact configuration and load current.

We cross-reference parameters against official TE Connectivity Potter & Brumfield technical documentation to confirm electrical and mechanical interchangeability, providing commercial pricing, lead time and international delivery options.

Potter & Brumfield and model names are trademarks of their respective owners and are used only to identify the equipment for which we source parts. SpareX is not an official dealer, distributor or representative of Potter & Brumfield and is not affiliated with the trademark owner. Origin, documents and warranty are stated for each item in the quotation.