Epcos

Epcos capacitors for pool pump and motor circuits

Epcos is a name associated with passive electronic components, and capacitors in particular. In a swimming pool installation those components turn up in one place above all: the terminal box or housing of a single-phase pump motor, where a capacitor is needed to get the motor turning and to keep it running smoothly. Here you will find the Epcos capacitor stocked for that purpose, along with the information needed to check that it matches the one already fitted.

What the capacitor does in a pool pump

Most domestic filtration pumps, heat pump fans and small booster pumps run from a single-phase supply. A single-phase induction motor cannot produce a rotating field on its own, so a capacitor is wired to an auxiliary winding to shift the phase and create starting torque. On many pool pumps the same capacitor stays in circuit while the motor runs, which means it is under electrical stress for every hour the filtration cycle is active.

Capacitors are therefore a classic wear part rather than a permanent fitting. The symptoms of a tired one are easy to recognise: the motor hums but will not spin until the shaft is nudged, it starts slowly or trips the breaker, it runs hot or noisy, or the capacitor body itself has swollen at the top or shows signs of having vented. A pump that has stopped working after years of reliable service very often needs nothing more than a new capacitor and a check of the winding resistance.

The range in brief

The Epcos range listed here is deliberately narrow and covers one common value:

• 10µF capacitor with spade connectors – PPS-10063, a 10 microfarad unit terminated with flat spade tabs so it can be connected with push-on receptacles rather than screw terminals.

Ten microfarads is a value frequently encountered on smaller single-phase filtration pumps and on fan motors, but capacitance is specific to the motor it was designed around. Always read the value from the component being replaced rather than assuming it from the pump size.

Choosing the right capacitor

Everything needed to identify a replacement is printed on the side of the original. Before ordering, note the following:

• Capacitance – the µF figure must match the original. Fitting a higher or lower value changes the phase shift and can leave the motor under-torqued or running hot.
• Tensiune nominală – the working voltage printed on the body must be equal to or higher than that of the part being replaced. Never fit a lower-rated component.
• Terminal type – spade tabs accept push-on connectors, while other capacitors use screw terminals or flying leads. Check which style the motor loom expects, and whether the existing wiring can simply be transferred across.
• Body dimensions – measure the diameter and the height of the can. Terminal boxes and capacitor clamps are often tight, so a physically larger replacement may not fit even if it is electrically correct.
• Mounting – some capacitors sit loose in a box, others are held by a strap or by a threaded stud in the base. Confirm how the original is retained.
• Run or start duty – start capacitors are designed for short bursts only and are not interchangeable with run capacitors that stay energised throughout operation.

Fitting and handling safely

Electrical work on pool equipment should be carried out by a competent person and in line with local wiring regulations. Isolate the supply at the consumer unit before opening any terminal box, and remember that a capacitor can hold a charge after the power has been switched off; it should be discharged safely across its terminals before being handled. Photograph or label the wiring before disconnecting anything, since the auxiliary winding and supply connections are easy to confuse once the leads are off.

While the housing is open it is worth checking the condition of the terminal box gasket, the cable gland and the motor shaft seal area. Moisture ingress is a frequent cause of repeat electrical failures around pool plant, and a new capacitor will not last long in a wet enclosure.

Epcos at PoolParthub.com

Here we list the Epcos capacitor used as a service part in single-phase pool pump and fan motor circuits, supplied as an individual component so that a working pump does not have to be replaced because of one failed part.

Customers across Europe order from us for repairs of exactly this kind, where the difficulty is less in the fitting than in finding the right value and terminal style. If the figure on the original is unreadable, the motor data plate or the pump documentation will usually confirm the capacitance required.