Milesight TS201 vs TS302: one probe or two?

Short answer: The TS201 has one M12 connector and takes a single temperature probe. The TS302 has two, so it can carry two probes, or one probe plus a magnet switch that reports the door opening – which is what makes it the HACCP fridge configuration. Both are LoRaWAN Class A sensors on EU868, both are certified to EN12830 for cold chain, and both use the same 5-pin M12 A-coded fitting. Take the TS201 for one measurement point per unit; take the TS302 when one location needs two readings on a single device.

TS201 vs TS302: which one do I need?

Choose the TS201 if each fridge, freezer or store room needs one temperature reading and nothing else. It is the smaller unit – 58 x 65 x 25 mm and 70 g against 109 x 75 x 29 mm and 185 g – it is rated IP67 rather than IP65, it runs on a single ER14505 cell, and it is the cheaper of the two.

Choose the TS302 if one location needs two readings, if someone has to read the temperature standing in front of the unit, or if you need a probe range the TS201 cannot reach. It has an LCD segment screen, logs 10,000 measurements with CSV and PDF export named in its datasheet, runs on two ER18505 cells or Type-C USB, and its optional PT100 probes are listed down to -200 °C and up to 500 °C – well outside the TS201 probe’s -40 °C to 125 °C.

Several specs people expect to separate them do not. The radio is the same on paper: identical frequency list including EU868, 16 dBm at 868 MHz, -137 dBm sensitivity at 300 bps, Class A OTAA/ABP and Milesight D2D on both. Accuracy belongs to the probe, not the transmitter – fit the same DS18B20 or CMOSens type and the quoted figures match. And at SF10 on EU868 the quoted battery life is close: around 2.7 to 2.8 years for the TS201, over 2.7 years for a TS302 carrying two probes.

What does the second connector actually buy you?

Milesight’s datasheet is specific about what the TS302’s two ports will take: two temperature/humidity sensors, or one temperature/humidity probe plus a magnet switch sensor. That second combination is the HACCP fridge build – the SS21-PN03-150 magnet switch (20-30 mm detection, two switches, 1.5 m cable) tells you the door opened, so an excursion in the log arrives with its own explanation. On list price, one TS302 sits below two TS201s.

Three things it is not. The TS302 is not two sensors – one device, one battery, one LoRaWAN join, so two probes cost you one node on the network server rather than two. It will not take two magnet switches; one port must carry a temperature/humidity probe. And it is not a TS201 with a spare socket – different enclosure, IP65 rather than IP67, and its probes are listed as separate part numbers (SP12-125-150, SP13-125-150, the PT100 variants, SS21-PN03-150), so confirm the probe combination when you order.

Does the -40 °C rating mean I can put the sensor in the freezer?

No, and this is the one to get right. The -40 °C to 125 °C figure is the probe range. The transmitter body is rated -30 °C to 55 °C on the TS201 and -30 °C to +70 °C on the TS302. The probe goes into the cold space on its 1.5 m cable and the transmitter stays outside it – that is what the detachable probe is for. EN12830 on both units does not change where the electronics can sit.

Milesight TS201 Temperature Sensor – TS201-868M (temperature probe)

TS201-868M

£44.89 ex VAT (£53.87 inc. VAT)

View the TS201-868M

Milesight TS302 Temperature Sensor – TS302-868M (2 channels)

TS302-868M

£73.32 ex VAT (£87.98 inc. VAT)

View the TS302-868M