BLOCK External Temp — WiFi temperature logger with external probe

Frequently asked questions

What is the difference between the EDGE and BLOCK families?

EDGE is the sealed, display-equipped line: ambient temperature and humidity, external probes down to -55 C, CO2, plus pharmacy and in-transit variants. Every EDGE unit has an on-screen display, an audible buzzer and a visible on-device alarm, and most models come in matched WiFi and cellular pairs. BLOCK is the industrial and retrofit line: one compact WiFi housing with sensor ports for fluid pressure, current clamps, pulse counting, 4-20 mA loops, differential pressure and light. The principle is swap the probe, not the device, because calibration lives with the plug-in sensor, so recertifying means a new probe rather than an RMA.

What can the BLOCK models actually measure?

BLOCK models share one WiFi housing and differ by what plugs into the ports. BLOCK Essential logs ambient temperature and humidity with leak and door-contact inputs. External Temp and THERMO II take one or two detachable probes for -55 C to +125 C. The rest measure CO2, barometric pressure, differential pressure for cleanrooms and filter loading, fluid line pressure and temperature, light intensity, motor and compressor current through a split-core clamp, dry-contact meter pulses, and any industrial 4-20 mA transmitter. Every BLOCK also reports its own ambient temperature and humidity.

What do I need before I install a logger?

A free LF Cloud account and the device label. Go to app.LoggerFlex.com, create and verify the account, then add the device using its Serial Number and DUID. On EDGE you can scan the QR on the display to fill both in; on BLOCK they are printed on the label at the back; on CORE, press the gear button and they appear on screen for three minutes. The registration wizard sets the recording interval, syncing interval and alarm thresholds and pushes them down on first connection. Register before setup — on BLOCK, before you even power the unit.

How do I connect a logger to Wi-Fi?

Register the device first, then press the SETUP button — the right button on EDGE, the top button on BLOCK. The logger raises a temporary Wi-Fi network called Datalogger. Join it from a phone, tablet or laptop. A setup page opens on its own; if it does not, browse to 8.8.8.8. Pick your 2.4 GHz network, type the password and connect. The device then pulls its logging settings and thresholds from LF Cloud. Press SYNC — left button on EDGE, bottom on BLOCK — to force an upload and confirm it is online.

What are the network requirements for a Wi-Fi logger?

2.4 GHz only — 5 GHz is not supported. That is deliberate: 2.4 GHz carries further through concrete and steel, which is what industrial sites are made of. The network must use a WPA or WPA2 pre-shared key and hand out addresses by DHCP; static IP is not supported, and the password is case-sensitive. The device cannot join a network with a captive portal or a secondary login page, which rules out most guest, hotel and campus SSIDs. Dual-band routers and mobile hotspots are fine as long as a 2.4 GHz SSID is reachable.

Do I need a gateway, hub or bridge?

No. Every EDGE and BLOCK unit reaches LF Cloud on its own — BLOCK and Wi-Fi EDGE models over your existing Wi-Fi, cellular EDGE models over their built-in modem — so there is no proprietary gateway to buy, mount or maintain and no IT project to schedule. The cellular water meter works the same way, with its own 4G modem and managed SIM. EDGE also broadcasts Bluetooth for local viewing, and that is the single exception: a LoggerFlex gateway is needed only to capture BLE data. Logging, alarms and cloud reporting all work without one.

How quickly does data reach the dashboard?

Two independent clocks run. The recording interval decides how often the device measures and stores a reading locally; the syncing interval decides how often it uploads. A device can look quiet simply because its next scheduled upload has not happened yet. Alarms bypass the sync clock entirely — a threshold breach forces an immediate sync, drops recording to once a minute and sounds the buzzer for five seconds. Shortening the sync interval does not make alarms faster, it only costs battery. EDGE units left on USB-C power sync every 15 minutes.

What happens if the internet drops — do I lose readings?

No. The logger keeps measuring and stores every reading with its timestamp in internal memory, then uploads the whole backlog automatically the next time it connects, so the history closes with no gaps. If a scheduled upload is missed, LF Cloud sends a Missing Upload email so you know a device has gone quiet. One caution for sites with poor coverage: an alarm raised while the device is offline makes it retry repeatedly and drains the batteries fast, so use Battery Saving sync mode and leave alarms off where you are logging without a connection.

How long do the batteries last?

Up to 3 years on 4 AA batteries, using a power-management architecture protected by US Patent US11455877B2. That is the rated figure published for the EDGE Wi-Fi loggers, and BLOCK is specified at up to 36 months on cells. EDGE units with an E-INK display typically run two to three years in the field, and EDGE Lite is rated up to two years. Real-world life depends on your recording interval, sync interval, alarm activity, signal quality and ambient temperature, so we size it against your actual deployment.

What actually shortens battery life on site?

Four things. Recording and sync intervals: logging every minute and uploading every hour drains far faster than the defaults. Alarm activity, because every transmission powers the radio. Weak Wi-Fi signal, which forces the device to retransmit packets. And temperature, since extreme cold or heat reduces cell efficiency. Leave the default intervals alone unless you have a reason to change them. A shorter sync interval does not make alarms arrive faster, because an out-of-range reading never waits for a scheduled upload.

Can I run a logger on mains power instead of batteries?

Yes. EDGE Essential, Thermo, Pharma and Air run on 4 AA cells or USB-C 5 V and switch automatically based on what is available, so the cells become backup rather than the primary source. BLOCK is offered with a USB-C power option as well. One behaviour worth knowing: while an EDGE unit is plugged in it drops its sync interval to 15 minutes automatically, so your chart fills in through the day instead of once at the scheduled send. Alarm speed is unchanged either way.

Will I be warned before the batteries go flat?

Yes. The cloud emails a low-battery alert while there is still life in the cells, not once they are dead. Separately, if a device misses a scheduled upload you get a Missing Upload email, which catches a flat battery, a dead router or a unit someone unplugged. EDGE also shows battery level and external-power status on the device display, and the app carries a battery icon for each device. Email alerts are free and unlimited; routing them to SMS or a phone call draws on the device credit.