Memmert SN55plus Hot-Air Steriliser, 53 L, Natural Convection, TwinDISPLAY – Class IIb medical device

The Memmert SN55plus hot-air steriliser sterilises medical materials using dry heat at atmospheric pressure – as a Class IIb medical device (in accordance with MDD 93/42/EEC), it is suitable for small practice laboratories, dental and medical practices, as well as school and training laboratories. With an internal capacity of 53 litres and a temperature range of +20 °C to +250 °C, the unit is particularly suitable when only a few instruments or small quantities of powders and granules need to be sterilised and worktop space is limited. The combination of certified medical device classification and a validatable sterilisation process supports the requirements for traceability and documentation, as is standard in the quality management systems of medical practices, clinics and laboratories.

Natural convection instead of forced air circulation

Unlike the Memmert SF series, the SN55plus operates using natural ventilation rather than an electronically controlled recirculation fan. Preheated fresh air is introduced via an electronically adjustable exhaust air flap, whilst an exhaust air outlet with an adjustable damper ensures controlled air exchange – entirely without any active air movement inside the chamber. This makes the SN series the preferred choice wherever powders, granules or light, exposed instruments could be stirred up or contaminated by a forced air flow.

Precise temperature control with SetpointWAIT

The TwinDISPLAY version, the SN55plus, provides additional safeguards for this process: two independent Pt100 sensors using a 4-wire measurement method monitor the temperature in a redundant configuration – if one sensor fails, the second seamlessly takes over control. The SetpointWAIT function only starts the sterilisation time once the setpoint temperature has actually been reached – ensuring validatable, reproducible cycles, as required for quality management documentation in dental and clinical hygiene, as well as in microbiological and pharmaceutical laboratories.

Safety and Features

• Electronic temperature monitoring plus mechanical temperature limiter, protection class 1 (DIN 12880)
• Self-diagnostic system for fault detection, visual and audible alarms
• Controller: TwinDISPLAY, adaptive multifunctional digital PID microprocessor controller with high-resolution TFT colour graphic display
• Digital countdown timer with target time setting, adjustable from 1 minute to 99 days

Operation, interfaces and documentation

Programmes can be managed and log data from the data logger read out and archived via the Ethernet interface or, optionally, via a USB stick using the AtmoCONTROL software – the programme sequence remains stored even after a power cut. This significantly facilitates comprehensive documentation in quality management, a criterion that is particularly important for validatable sterilisation processes in hospitals and laboratories. The built-in self-diagnostic system reports faults at an early stage via visual and audible alarms, so that deviations from the target process are not only noticed at the end of a sterilisation cycle, but can be detected and documented immediately.

Typical areas of application

• Sterilisation of instruments in medical practices and hospital hygiene
• Sterilisation of powders, granules and bulk materials without air movement inside the chamber
• Reprocessing of laboratory glassware and open vessels in microbiological and pharmaceutical laboratories
• Validatable, documented sterilisation cycles for quality management

This allows a small batch of instruments to be sterilised reliably and with full traceability in a single operation as part of day-to-day practice, without sensitive items being moved by air flow.

Technical details

Contents of delivery

• 1x Memmert SN55plus hot-air steriliser (basic unit)
• 2x stainless steel wire racks (electropolished)
• 1x factory calibration certificate (at +160 °C)

Regulatory information

WEEE registration number (manufacturer Memmert): DE 66812464. As an electrical appliance, the SN55plus is subject to the ElektroG (WEEE Directive) – registration is held by the manufacturer Memmert, as they are the first to place the appliance on the German market, not by LT Laborhandel as the distribution partner.

Customised requirements & procurement service

Do you require additional accessories such as further stainless steel grids, a bespoke calibration or spare parts? Our procurement service will be happy to assist you with any special enquiries regarding the SN55plus.