Sentry
Sentry ST633 Thermal Imager -35~630°C 12:1 DS ratio
Compact thermal imager measures -35 to 630 °C with 12:1 spot ratio and selectable emissivity
- Color/FinishRed
- Item Count1 pack
- Selling UnitBox
- Parts3 Years
- Labor1 Year
- Wide range -35 to 630 °C for diverse tasks
- 12:1 distance-to-spot ratio measures small targets far away
- Selectable emissivity 0.95 0.70 0.30 suits different surfaces
- Fast 500 ms response gives quick readings
- Compact 156×100×32 mm and 136 g fits in a pocket
Compact thermal imager for electrical diagnostics
The Sentry ST633 is a pocket-sized thermal imager built for electricians and maintenance technicians who need fast, non-contact temperature checks on panels, motors and HVAC equipment. It measures from -35 to 630 °C with a 12:1 distance-to-spot ratio and a 500 ms response time. A selectable emissivity of 0.95, 0.70 or 0.30 lets you adapt to different surface materials.
Suits spot checks on live circuits.
This tool fits technicians who carry out periodic inspections and want a lightweight device that fits in a tool bag. The auto power-off after roughly six seconds saves battery life during intermittent use. It is not intended for users who need data logging, image capture or a wider temperature span beyond 630 °C.
12:1 distance-to-spot ratio sets the measurement
At the 12:1 ratio the measurement spot grows one unit wide for every twelve units of distance, so accurate readings on small components require working relatively close. The fixed emissivity choices of 0.95, 0.70 and 0.30 cover common electrical surfaces but cannot be tuned for unusual coatings.
Highlights
- Wide range -35 to 630 °C for diverse tasks
- 12:1 distance-to-spot ratio measures small targets far away
- Selectable emissivity 0.95 0.70 0.30 suits different surfaces
- Fast 500 ms response gives quick readings
- Compact 156×100×32 mm and 136 g fits in a pocket
Specifications
| Brand | SENTRY |
|---|---|
| Model | ST633 |
| Color/Finish | Red |
| Item Count | 1 pack |
| Selling Unit | Box |
| Parts | 3 Years |
| Labor | 1 Year |
Questions about this item
How much heat does the ST633 generate when I leave it running all day?
The imager itself produces no measurable heat; it draws power only from its own batteries and has an auto power-off after approximately 6 seconds of inactivity.
What must I supply before the ST633 will operate?
Batteries are not included, so you need to provide your own power cells before first use.
Can I keep using my older ST630 or ST632 accessories with the ST633?
The ST633 is a standalone unit with its own 12:1 distance-to-spot ratio and selectable emissivity settings of 0.95, 0.70 and 0.30; no accessories from earlier models are required or referenced.
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