Reefer monitoring, and what it tells you

Reefer monitoring is the carrier’s readout of what the refrigeration unit is doing while your container is in transit — air temperatures, alarm state, power, and on most services a position. It reports the machine, not the fruit inside it.

Every reefer has always recorded its own temperature. What changed is that newer boxes carry a modem and push those readings off the vessel instead of holding them until arrival. The lines wrapped that in a service and gave it a name — Captain Peter at Maersk, Live Reefer at Hapag-Lloyd — and what reaches you is a portal, an email alert, or an API feed.

What it does and does not tell you #

You get delivery air and return air temperature, whether the unit is in alarm, and whether it has power. On a controlled atmosphere booking it usually adds oxygen and carbon dioxide levels.

You do not get pulp temperature, which is what the fruit is actually doing. A container stuffed warm reports a flawless voyage while the cargo sits above specification for days.

Three limits are worth knowing before you plan around it:

• Coverage follows the box, not the brochure. Whether readings arrive depends on the age of the container you were allocated, not on the line’s marketing.
• Sampling intervals differ. An hourly reading and a six-hourly one are not the same evidence in a claim.
• It does not follow the booking. Book through a forwarder rather than directly with the line and the portal belongs to somebody else’s account.

None of it replaces the full log downloaded on arrival. That is still the document that settles a quality dispute.

Where it sits next to tracking #

Monitoring answers “how is the box”. Tracking answers “where is it, and when does the clock start”. Importers on carrier-owned reefers usually run both: the line’s monitoring for condition, and a tracking platform for milestones, ETA movement and the discharge event that starts free time. Trackberry does the second and does not read the unit, so the two sit side by side rather than one replacing the other.

FAQ #

Does reefer monitoring tell me whether the fruit is still good? #

No. It tells you what the air in the container did, which is the closest proxy you have in transit and not the same thing. Fruit loaded warm, packed badly or already past its best gives a perfect readout all the way to the quay.

Do I still need the temperature log on arrival? #

Yes, every time. Monitoring is a sample at whatever interval the line pushes; the log is the complete record, and it is the version a claim is argued over. Pull it before the empty goes back.

Why does my container have no monitoring data? #

Most often because the box you were allocated has no modem — fleets are fitted gradually, and allocation is not something you control. The other common reason is that you booked through a forwarder, so the data reaches their account and not yours.