TL;DR: A LoRaWAN site survey measures the radio link between a gateway and every place a sensor will go, before the sensors are bought and fitted. You put a gateway where it will live, walk the site with a field tester such as the Milesight FT101, and record signal strength, signal to noise ratio and…
TL;DR: The Milesight EG71 is a building gateway that reads wired building protocols (Modbus RTU and TCP, BACnet MS/TP and IP, KNX) and LoRaWAN sensors in one DIN rail box, adds its own inputs and outputs, and passes everything on over BACnet/IP, Modbus TCP, MQTT or HTTP. It earns its price when a building has…
TL;DR: Many gas and electricity meters already emit a pulse for every fixed quantity of energy or gas they measure. A pulse counter counts those pulses and sends them to a dashboard, so an existing meter becomes a live data source without being replaced. The value of each pulse is printed on the meter, and…
TL;DR: UK law says the temperature in an indoor workplace must be reasonable during working hours. The Approved Code of Practice puts the minimum at 16°C, or 13°C for strenuous work, and there is no legal maximum, because heat is treated as a hazard to be risk assessed instead. Less well known, the Workplace Regulations…
TL;DR: HSG274 does not ask you to run a tap for a fixed number of minutes. It asks you to flush until the temperature at the outlet stabilises and is comparable to supply water. That means the legionella flushing test is, literally, a temperature measurement. It is also the one control almost every estate records…
TL;DR: The PSTN switch-off completes in January 2027, when the analogue telephone network that has carried voice, alarms and dial-up data for decades is retired. The government’s own list of affected equipment names alarms, lifts, payment terminals and intercoms. On industrial and estates sites the risk hides in things nobody calls a phone: alarm diallers…
TL;DR: ASHRAE recommends an inlet air temperature of 18 to 27°C for every class of IT equipment, with humidity held below 60% RH. The part of the room that punishes a warm day hardest is the UPS: lead acid batteries lose roughly half their life for every 8 to 10°C above 25°C. So the server…
TL;DR: The UK’s statutory river standard for oxygen is not an average. It is a 10 percentile, which means the classification is decided by the worst tenth of the readings. In a river those readings happen shortly before dawn, when nothing has photosynthesised for eight hours and everything has carried on breathing. A grab sample…
TL;DR: A pressure transient travels along a metal water main at around 1,000 metres per second and is over in a fraction of a second. A logger sampling every 15 minutes has roughly a one in a million chance of being awake when it passes. The interesting part is what the UK’s own review concluded…
TL;DR: 4-20mA is the only industrial signalling standard that has survived every wave of digitalisation, and it survives for one reason. A healthy loop never reads zero. Four milliamps is the bottom of the scale, so nought milliamps cannot be a measurement, it can only be a broken wire, a pulled terminal or a dead…