Magnetic detector for doors and windows SATEL B-21 recessed hermetic NC diameter 6.5 mm
- The hermetic magnetic (reed switch) sensor of NC type for recessed mounting, is used to detect the opening of doors and windows; the contact closing distance is 19 mm.
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B-21 hermetic magnetic detector with flange for recessed mounting
The B-21 magnetic detector from SATEL is a hermetic reed detector with a square flange, designed for recessed mounting in elements such as doors and windows. The device comes with a magnet holder for easy installation in hard-to-reach places and is available in white (B-21) and brown (B-21 BR) versions.
- Hermetic reed detector for perimeter protection
- Recessed mounting with square flange
- Diameter of detector housing 6.5 mm
- Operating temperature range from -10 to +55 °C
- Distance of closing reed switch contacts 19 mm and opening 24 mm
Intended use and application
The B-21 detector is a component of burglary and robbery alarm systems, designed for perimeter protection, in particular for monitoring the opening status of doors, windows and similar movable elements. Thanks to its hermetic construction and the use of an NC-type reed switch, the detector provides reliable detection of violation of the protected zone in typical environmental conditions in accordance with environmental class II according to EN50130-5.
The detector is accompanied by a magnet holder, which allows convenient installation also in hard-to-reach places, ensuring proper positioning of the magnetic element in relation to the reed switch housing. The model comes in two color versions: white (B-21) and brown (B-21 BR), which allows the element to match the color scheme of the door or window woodwork.
Construction and installation
The B-21 has a medium-sized hermetic housing with a square flange, which facilitates aesthetically pleasing recessed installation in a substrate such as a window frame or door frame. The reed switch housing measures 26 x 10 x 10 mm, while the flange has a side length of 10 mm, which ensures stable seating of the element in the prepared mounting hole. The diameter of the housing is 6.5 mm, so the detector can be used in relatively narrow profiles.
The dimensions of the magnet's housing are 19 x 7.6 mm, and the included 55 x 12.6 x 19.8 mm bracket facilitates its installation in various structural configurations. The cable length is 450 mm, which gives the installer some freedom to run wiring to the control panel or connection strip. The manufacturer stipulates that the actual appearance of the product may differ from the presented photos, and the descriptions are for informational purposes.
Technical specifications
| Parameter | Value |
|---|---|
| Device type | Hermetic magnetic (reed) detector for recessed mounting |
| Purpose | Burglary and assault signaling, perimeter protection detector for doors, windows, etc. |
| Color versions | B-21 (white), B-21 BR (brown) |
| Detector type | NC |
| Detector housing diameter | 6.5 mm |
| Dimensions of reed switch housing | 26 x 10 x 10 mm |
| Flange dimensions | square flange, side 10 mm |
| Magnet housing dimensions | 19 x 7.6 mm |
| Dimensions of magnet holder | 55 x 12.6 x 19.8 mm |
| Contact closure distance of the reed switch | 19 mm |
| Distance of opening of reed switch contacts | 24 mm |
| Maximum switchable voltage | 100 V |
| Maximum switchable current | 500 µA |
| Maximum load power | 10 W |
| Maximum contact resistance | 200 Ω |
| Cable length | 450 mm |
| Operating temperature range | -10...+55 °C |
| Maximum humidity | 93 ± 3% |
| Environmental class according to EN50130-5 | II |
| Weight | 13 g |
Technical data source:data sheet for model B-21 Link
FAQ - the most common questions about the B-21
What is the type of the B-21 detector?
B-21 is a hermetic magnetic (reed switch) detector of NC type, designed for use in intrusion alarm systems.
For what use is the B-21 detector designed?
The B-21 detector is designed for perimeter protection, primarily for detecting the opening of doors, windows and similar moving elements.
How is the B-21 detector mounted?
The B-21 is a recessed-mount detector, installed in a drilled hole in the door or window frame, using a square flange.
What color versions of the detector are available?
The detector comes in two color versions: white marked as B-21 and brown marked as B-21 BR.
What is the operating temperature range of the B-21 detector?
The operating temperature range of the B-21 detector is -10 to +55 °C.
What are the dimensions of the reed switch housing?
The reed switch housing of the B-21 detector has dimensions of 26 x 10 x 10 mm.
What is the diameter of the detector housing?
The diameter of the housing of the B-21 detector is 6.5 mm.
What are the dimensions of the detector's flange?
The flange is square with a side of 10 mm, which facilitates stable embedding in the ground.
What are the tripping distances of the reed switch?
The closing distance of the reed switch contacts is 19 mm, while their opening distance is 24 mm.
What are the dimensions of the magnet housing?
The magnet housing that works with the B-21 detector has dimensions of 19 x 7.6 mm.
What are the dimensions of the magnet holder?
The dimensions of the magnet holder are 55 x 12.6 x 19.8 mm.
How long is the detector's wiring harness?
The length of the wires attached to the B-21 detector is 450 mm.
What is the maximum switching voltage of the contacts?
The maximum switchable voltage of the reed switch contacts in the B-21 detector is 100 V.
What is the maximum switching current?
The maximum switching current of the contacts is 500 µA.
What is the maximum contact load power?
The maximum contact load power of the reed switch contacts of the B-21 detector is 10 watts.
What is the maximum contact resistance?
The maximum resistance of the reed switch contacts of the B-21 detector is 200 Ω.
In what environmental class does the B-21 detector operate?
The B-21 detector operates in environmental class II according to EN50130-5.
What is the maximum operating humidity of the detector?
The maximum operating humidity of the B-21 detector is 93 ± 3%.
What is the weight of the B-21 detector?
The weight of the B-21 detector is 13 g.
B-21 is a recessed-mounted hermetic NC-type magnetic detector for perimeter protection of doors, windows and similar items. The device is characterized by compact dimensions, defined tripping distances and electrical parameters described in the manufacturer's data sheet.