Cooling fans in cabinets and equipment rooms
A fan that stops is the first step towards a site going down on heat. A tag inside the cabinet reports the fan's level and alerts the moment it drops, well before the temperature alarm that follows.
Sound level monitoring tag
The ZARC sound level tag reports how loud a place or a machine is, in real time, and alerts when the level rises above a limit you set or falls below one. Too loud means a complaint, a breach or a machine in trouble. Too quiet means a fan, pump or generator has stopped. The tag is small enough to sit inside the unit it listens to, runs on its own battery and reports a level, never audio.
01
What it reports
The tag reads sound level continuously in dB(A), the weighting that follows human hearing, and reports at the interval set for the site, down to every minute. Each report can carry the current level, the maximum, the minimum, the average and the peak for that interval, so a short loud event between reports is not lost.
Alerts work in both directions. A high limit catches noise: a site over its agreed level, plant running louder than it should. A low limit catches silence: a cooling fan that has stopped, a generator that failed to start, a pump that is no longer running. Where a unit should always be making a sound, no sound is the alarm.
Duration decides what matters. An alert can wait until the level has stayed above or below a limit for a period you choose, so a passing lorry or a door slamming does not raise it, and ten minutes without a fan does.
Machinery usually changes its note before it fails. A bearing wearing, a fan out of balance or a loose panel shows as a level creeping up over days, or as peaks that were not there last month. The dashboard keeps the full history, so the change is on the graph before anyone has to stand next to the machine to hear it.
The tag reports numbers only. Nothing is recorded and no audio leaves it, which is why it can be fitted in homes, wards and offices where a recording microphone would never be accepted.
02
Applications
Sound tells you two things about a site: whether it is disturbing anyone, and whether its equipment is running as it should. The uses below are a starting point; the same tag works wherever a level, or a silence, means something.
Proof that plant is running
Generators, pumps, compressors and extract fans all make a steady sound while they work. A low limit turns that into a running signal with no connection to the equipment and no access to its controls.
Machinery starting to fail
A unit that runs louder than it did, or produces peaks it never used to, is telling you something. The level history shows when the change began and how fast it is growing, so the visit is planned and not an emergency.
Learning what normal sounds like
Months of level history are a data set. A unit's normal running profile can be modelled and departures from it flagged, as a bespoke project built on the same readings.
Noise complaints
When a neighbour says a site is too loud, the answer is a dated record: the maximum level, hour by hour, for the period in question. It settles whether the site was loud, when, and for how long.
Infrastructure close to homes
Cooling plant, substations and equipment compounds near housing draw complaints whether or not they are the cause. A continuous record of what the site emits is the operator's own evidence.
Construction site noise
A live level at the boundary against the hours and limits agreed for the works, with alerts to the site team before a limit becomes a breach.
Local alarm sounders
In an unattended building, an alarm that only sounds on site is heard by nobody. A sustained loud level raises an alert. Where the panel has an output, the alarm relay tag is the better choice.
Data halls and comms rooms
Air handling and cooling units have a steady signature. A unit going quiet, or one working harder than the rest, shows on the dashboard beside the temperature.
Short lets and shared housing
An alert when a property is loud late at night, with no recording and nothing said captured.
03
Where it can go
The tag is small, has no cable and needs no socket, so it goes where the sound is. Typical positions:
Inside equipment cabinets
Beside the fan tray, to confirm airflow by sound.
Inside a unit's housing
Within a generator canopy, chiller or air handling unit, next to the motor or fan.
Plant rooms
On the wall near the machine whose normal level is the baseline.
Site boundaries
On fencing or hoarding facing the nearest neighbour.
Building exteriors
Under eaves or on a wall facing a yard or compound, in an enclosure specified for weather.
Occupied rooms
High on a wall or ceiling in corridors, wards and shared spaces.
04
In the dashboard
Every tag shows its live level and a trend running from the last hour to the last year. The dashboard works out the maximum, minimum and average over any period, the peaks, and how long the level has spent above or below each limit. Quiet periods are shown as clearly as loud ones, so a unit that stopped at 3 am is as visible as a site that was loud at 3 pm. Every reading is time-stamped and exports as a record for a complaint, a client or a regulator.
Limits are set per tag: high, low, duration, and different values by time of day. When one is crossed the alert is raised in real time and goes by email or SMS, and through an app where required, to the people you name, with escalation to further contacts.
- Live level for every tag, grouped by site
- Trend graphs from one hour to one year
- Maximum, minimum and average over any period
- Peak levels and when they happened
- Time spent above or below each limit
- Quiet periods where a unit should have been running
- Day, evening and night limits on the same tag
- Every alert logged with the reading that raised it
- Records exported with dates and times
- A tag that misses its reporting interval is flagged
05
Industries
Sound matters wherever equipment runs unattended or noise has a neighbour, including:
Telecoms infrastructure
Fans and cooling in cabinets and compounds, and the level a site emits.
Data centres and critical infrastructure
Cooling and air handling units running as they should.
Energy and utilities
Substations, pumping stations and plant near housing.
Industrial and manufacturing
Machines that change their note, and levels across a production floor.
Construction and temporary works
Boundary levels through noisy phases.
Facilities management
Plant rooms and noise complaints across a portfolio.
06
Technical specification
| Parameter | Specification |
|---|---|
| Measurement | Sound level, read continuously and reported in real time |
| Sensor | Microphone inside the tag; level only, no audio recorded or transmitted |
| Units | dB(A) |
| Values reported | Current level, maximum, minimum, average and peak for each reporting interval, set per tag |
| Range and accuracy | Specified to the requirement |
| Reporting interval | Configurable, down to every minute |
| High-level alerts | Level above a limit you set |
| Low-level and silence alerts | Level below a limit, or no sound, where a unit should be running |
| Duration alerts | Time above or below a limit, so a passing noise does not alarm |
| Trend alerts | Level rising over days or weeks, at a rate you set |
| Time-of-day limits | Separate limits for day, evening and night |
| Alert delivery | Dashboard, email or SMS; app where required |
| Recipients | Named people and groups, with escalation to further contacts |
| Missed reports | A tag that misses its reporting interval is flagged in the dashboard |
| Gateway power loss | Raises its own platform alert |
| Dashboard | Live level, trends, max/min/average, peaks, time above and below limits, quiet periods; configured to your requirement |
| Records | Every reading and alert time-stamped and exportable |
| Data | Full reading history; UK-hosted or on servers on your own site |
| Power | Internal battery, up to five years depending on reporting interval |
| Radio | 433 MHz, one-way (transmit only) |
| Radio range | Site-dependent; confirmed by site survey |
| Size | Small enough to fit inside a cabinet, canopy or equipment housing |
| Mounting | Wall, ceiling or boundary, or inside the unit it listens to |
| Environment | Indoor or outdoor, enclosure specified to the location |
| Enclosure | Standard or built to the site; bespoke moulding for volume orders |
| Charges | No per-alert, per-user or licence charges |
| Manufacture | Made to order in the UK |
| Certification | CE marked |
07
From requirement to live alerts
Requirement
Tell us what you need to hear about: a site that is too loud, a unit that has gone quiet, or a machine that is changing. That decides where the tags go and which limits matter.
Configuration
Each tag is built to order with its reporting interval, the values it reports, and its high, low and duration limits.
Fitting
The tag is fixed in place in minutes, on a wall, at a boundary or inside the unit. No cable, and no connection to the equipment.
Commissioning
The normal running level is recorded as the baseline, limits are set against it, and the unit is stopped and started to prove the silence alert before the alert routes are tested.
Ready to get started? Every deployment begins with a site survey.
Book a site survey08
How it reports
Each reading goes over 433 MHz radio to a ZARC gateway and on to the dashboard, where limits and durations are checked and alerts are sent. The tag has a transmitter and no receiver, so nothing can reach it or change its settings over the air. A tag that stops reporting is flagged, so a missing tag is never mistaken for a quiet site.
Related tags
Temperature
The heat that follows a failed fan.
AC current
Whether a motor is drawing power.
Alarm relay
Takes an existing alarm output off site.
Light level
Whether a space is lit or dark.
Questions we answer most.
What does it measure?
Sound level in dB(A), read continuously, with the maximum, minimum, average and peak reported for each interval.
Does it record audio?
No. It reports a level only. Nothing is recorded and no audio leaves the tag.
Can it tell me a fan or machine has stopped?
Yes. A low limit raises an alert when the level drops or the sound stops where a unit should be running.
Can it warn me a machine is failing?
It shows the change. A unit running louder than its normal level, or producing new peaks, appears on the trend and can raise an alert.
Can it fit inside equipment?
Yes. The tag is small, battery powered and has no cable, so it sits inside a cabinet, canopy or housing next to the fan or motor.
Can the readings be used to answer a noise complaint?
Yes. Every reading is time-stamped and exportable, including the maximum level for any period.
Is it a calibrated sound level meter?
No. Where a consent, a standard or a noise-at-work assessment specifies a calibrated instrument, the tag does not replace it.
Will one loud bang set off an alert?
Only if you want it to. A duration alert waits until the level has stayed over the limit for a period you choose.
Can limits change by time of day?
Yes. Day, evening and night limits run on the same tag.
Does it need power or a network?
No. It runs on an internal battery and reports by radio to a ZARC gateway.
How long does the battery last?
Up to five years, depending on how often the tag reports.
Can it tell me what the noise is?
No. It reports how loud, when and for how long, not the source.
Looking for something else?
We work with any sensor for any application.
Most sensing needs are met by a tag we already build, configured for your equipment. If yours needs a sensor or interface we don't list, we have the engineering to build it. Tell us what you need to measure, and we will tell you how we would do it.
Discuss your requirementDiscuss a monitoring
or alerting solution
Tell us what is happening on site, what you need to see, and the event you need to hear about. We will come back with the system that answers it.
Direct contact
Location
Venator House, Unit 9, 15-17 St Stephen's Road, Bournemouth
Dorset, BH2 6LA · VAT GB 409644484
Products contact
Contact the engineering team
Direct to the team that designs and builds the range. Tell us the equipment and the event that matters.