Sentry
Sentry ST688 Infrared Thermometer 50:1 1000°C electrician tool
Non-contact infrared thermometer with 50:1 distance-to-spot ratio measuring up to 1000 °C
- Color/FinishRed
- Item Count1 pack
- Selling UnitBox
- Parts3 Years
- Labor1 Year
- Measures from a distance with 50:1 spot ratio
- Reads up to 1000 °C for high-heat tasks
- Detects down to -50 °C for cold environments
- Shows 0.1 ° resolution for fine detail
- Non-contact design keeps operator safe
Non-contact infrared thermometer
The Sentry ST688 is a non-contact infrared thermometer designed for electricians and technicians who need to measure surface temperature from a safe distance. It suits maintenance, electrical inspection and HVAC tasks where direct contact is impractical or hazardous.
50:1 distance-to-spot ratio
A 50:1 distance-to-spot ratio lets the user target small areas from further away, reducing the need to climb ladders or approach live equipment. The compact, rugged housing fits in a tool bag and leaves both hands free for probe work or safety gear.
Sustained high-range measurement
The instrument covers -50 °C to 1 000 °C with 0.1 °C resolution, maintaining consistent response during extended scanning sessions. It is not suited for processes exceeding 1 000 °C or for users who require data logging or wireless connectivity.
Highlights
- Measures from a distance with 50:1 spot ratio
- Reads up to 1000 °C for high-heat tasks
- Detects down to -50 °C for cold environments
- Shows 0.1 ° resolution for fine detail
- Non-contact design keeps operator safe
Specifications
| Brand | SENTRY |
|---|---|
| Model | ST688 |
| Color/Finish | Red |
| Item Count | 1 pack |
| Selling Unit | Box |
| Parts | 3 Years |
| Labor | 1 Year |
Questions about this item
How far can the 50:1 distance-to-spot ratio measure accurately?
The 50:1 ratio allows accurate non-contact measurements at long distances, suitable for electrical panels and industrial equipment.
Does the thermometer overheat during continuous daily use?
No internal heating components are present; the rugged compact design handles extended sessions without thermal drift.
What power source does the ST688 require to operate?
Standard batteries (not included) power the unit; no external supply or special charger is needed.
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