The PB series is the world’s smallest high performance motor protector.

The current and temperature sensing characteristics of the PB are tuneable to match the protection requirements of various intermittent and continuously rated 12V DC motors. The unique design gives an excellent on to off ratio resulting in reduced motor winding temperatures.

The PB design can provide a high level of current sensitivity with far lower switch resistance than any competing motor protectors, or the capability to carry a higher current for longer in a very small package, depending upon which configuration is chosen.

The PB is enclosed by an electrically insulated cover. The colour of the cover can be specified for easy identification in a busy factory. The terminals may be cropped and folded to suit the installation.



The PK series is the latest generation in high performance DC motor protectors, catering for trends in technical, quality & commercial requirements.

The PK offers higher performance, at a lower cost, in a small package size, plus high contact force and clean switching action on both opening & closing.

A full range of temperature & current sensitivity options are available. We offer PK variants capable of carrying up to 19A while switching 50A in a 12V DC motor, or switching as low as 3A. This can be achieved in ambient temperatures between -40°C and 90°C, while targeting a 4:1 on off ratio with a first remake time of <10s.

The PK is also suitable for 24V DC motors & despite the small package size will fulfil customers’ endurance tests switching up to 10A.

The PK is manufactured at high speed on a state of the art automated line. This ensures precision, cleanliness & consistent quality. Numerous terminal variations are available & colour ident for easy model differentiation.



The DA series is a more compact version of the Q series.

The DA series is an evolution of the well proven Otter Q Series offering the same excellent overcurrent and temperature protection for a wide range of 12 and 24 volt applications in a reduced package size.

DA offers slightly larger and more durable construction than the PK series, whilst providing comparable 24V performance.

The DA series is fitted with a coloured insulated cover and available in a range of folded and cropped terminal options.



The G series is Otter Controls’ most versatile bimetal switch.

The G Series is available in a wide range of formats such as thermostat, safety cut-out or DC motor protector and in many permutations of temperature setting, current sensitivity, cover and sealing options.

The G series can be set to temperatures ranging from 5°C to 155°C (165°C for DC applications) with controlled differentials and tolerances from ± 2°C in both normally closed and normally open configurations. There is also a range of bimetal resistivities to adjust the current sensitivity to suit the application.

The G series strong snap action makes it suitable for both 12V & 24V DC motors and 240V AC applications. While it is larger than later generations of motor protector, through its versatility it maintains a strong position within the Otter range.



The Q series is a larger and well established motor protector.

The Q series is larger & more robust than more recent generation motor protectors, with a greater contact gap on opening & closing, giving the Q capability to switch 16A in a 24V DC motor or 10(5)A at 250V AC.

Suitable for both intermittent and continuously rated motors, the Q Series offers a full range of current and temperature sensitive combinations to give optimum protection in any specific situation.

The Q is available in a range of folded & cropped terminal options. The insulated cover is in a variety of colours for product differentiation and there is the option of a plain cover or click fit, into the installation.



The T series is our highest current 24V motor protector, capable of switching up to 25A at 24V and 100A at 12V.

The T series is Otter Controls’ most robust and highest rated DC motor protector capable of switching up to 100A at 12V or 25A at 24V. A strong snap action and wide contact separation makes it ideal to cope with the high switching loads.

As with the smaller Otter motor protectors, the T series is available in a range of current and temperature sensitive combinations. There are also options for the cover and the terminal configuration.