Introduction to the SB-235 Solenoid Drop Bolt and its key features
The SB-235 Solenoid Drop Bolt is a purpose-built fail-safe mortice-style lock designed for concealed installation in timber and wood doors. Operating on 12 V DC, this power-to-lock solenoid bolt delivers a rated holding force of 1000 kg and includes practical features such as a selectable auto-relock timer (0 / 3 / 6 seconds), monitored detector plate and door-status output, and a low standby current draw. Supplied with a strike plate and fixings, the SB-235 is positioned for use in residential, commercial and light-industrial access-control systems where a neat, flush-fitting solution is required.
Key highlights at a glance:
- Fail-safe operation— unlocks when power is removed (suitable where safe egress on power loss is required).
- High holding force— 1000 kg rated hold for secure latching.
- Selectable relock timer— choose 0, 3 or 6 seconds delay to suit the access workflow.
- Monitored outputs— detector plate and monitored output provide door status feedback to access controllers.
- Concealed, mortice fit— flush appearance and discreet installation for timber doors.
Suggested retail price: 68.57 (currency implied). Supplier cost: 57.60. Warranty information is not specified in the available product details.
The SB-235 combines compact physical dimensions with robust mechanical performance and sensible electrical characteristics that make it straightforward to integrate into modern access-control setups. Below are the core specifications and what they mean in practice.
- Operating voltage: 12 V DC — widely supported by access controllers and power supplies used in security systems.
- Initial surge: 1.4 A; Operating current: 150 mA; Standby current: 100 mA — relatively low standby draw helps reduce running costs and heat generation in multi-door installations.
- Holding force: 1000 kg — a high-rated hold that offers strong resistance to forced entry when correctly installed and aligned with the strike.
- Delay timer: 0 / 3 / 6 seconds selectable — allows installers to tune how long the bolt remains withdrawn after release, accommodating card-reader workflows and timed egress sequences.
- Dimensions: 200 x 28 x 35 mm — compact mortice body to fit into timber door cavities.
- Weight: ~700 g (boxed); ~580 g (unboxed) — lightweight for a solid mechanical device.
- Finish: designed for concealed/flush fitting in timber doors for a neat aesthetic.
- Included in the box: solenoid bolt, strike plate and screws — standard installer accessories for a complete fit-out.
Benefits in real-world terms: the fail-safe design reduces the risk of occupants being trapped behind locked doors during power failures, the monitored output integrates easily with security management platforms for event logging and alarm conditions, and the selectable relock timing allows the device to support both immediate and delayed re-lock workflows depending on the application requirements.
The SB-235 is particularly well suited to situations where aesthetics, reliable holding force and integration with an access-control ecosystem are important. Typical scenarios include:
- Residential communal entry doors:where a flush, concealed lock is preferred for appearance, and monitored door status and timed release are used with intercoms or entry panels.
- Commercial offices and reception areas:internal doors that require secure control during business hours but safe egress on power loss or fire alarm activation.
- Light industrial storerooms and workshops:where a robust holding force is needed but the door substrate is timber rather than metal, making a mortice bolt a better aesthetic and mechanical match than large surface-mounted devices.
- Server rooms and equipment cupboards (non-locked-every-time applications):where monitored outputs can be used to log access events; note local regulation and IT policies should be checked for fail-safe vs fail-secure requirements.
- Integration with card readers, keypads or timed release panels:the selectable delay and monitored outputs make the SB-235 simple to tune for different entry workflows (immediate lock back vs allowing a short open period for two-person entry, for example).
In short, the SB-235 performs best where a discreet, timber-friendly solution with strong holding capability and system integration is required rather than a surface-mounted or heavy industrial locking device.
When evaluating the SB-235 you will commonly compare it to other solenoid bolts, electric strikes, and electromagnetic (mag) locks. Key differences include:
- Solenoid drop bolt vs mag lock:Mag locks rely on magnetic attraction and are usually surface-mounted, offering high holding force but often a bulkier appearance. The SB-235’s mortice design is concealed and generally preferred for timber doors and for a cleaner aesthetic. Mag locks can have comparable holding forces; however, they require uninterrupted, rigid frame surfaces and typically draw higher continuous current.
- Fail-safe vs fail-secure:The SB-235 is fail-safe (unlocks on power loss). Many electric strikes and some solenoid locks are fail-secure (remain locked without power). Choose fail-safe when safe egress on power cut is essential (or as required by local fire code); choose fail-secure where preserving lock state during power loss is critical to asset protection.
- Solenoid bolt vs electric strike:Electric strikes replace the strike plate and allow the existing mechanical latch to operate. The SB-235 is an active bolt that offers a dedicated high-holding mechanical latch — useful when you want an independent locking element rather than a strike that relies on the door’s latch.
- Energy and integration:The SB-235’s relatively low standby current (100 mA) and selectable relock timer make it efficient for multi-door installations and flexible for integration with controllers and access panels. Higher-power mag locks or some fail-secure devices may require larger power supplies and cooling considerations.
Trade-offs to consider: because the SB-235 is fail-safe, it may not be the right choice where the highest level of lock retention during power loss is required for security reasons. Also, the mortice installation requires routing into the door, which can add fit-out time compared with surface-mounted alternatives.
There are no customer reviews provided with the supplied product data. However, based on the SB-235’s specifications and common installer experience with similar devices, typical feedback themes likely to come from installers and end users include:
- Installers appreciatethe compact mortice body and included strike plate and fixings, which streamline door preparation and reduce the need for additional parts.
- System integrators valuethe monitored detector plate and door-status output for reporting and alarm integration — making it straightforward to link into access control software and building management systems.
- End users noticethe neat flush appearance in timber doors and the reliable feel of the bolt when engaging; the selectable relock timer is often highlighted as a useful, practical feature.
- Common improvement requests(from analogous product lines) can include clearer wiring diagrams in the box and an explicit warranty or certification statements — the SB-235 data indicates that compliance details should be checked in the manufacturer datasheet.
If you require genuine customer reviews for purchase decisions, ask your distributor for reference installations or seek installer testimonials specific to your region and use case.
The SB-235 Solenoid Drop Bolt offers a compelling mix of concealment, mechanical strength and system-ready features. Its 1000 kg holding force, low standby current, selectable relock timer and monitored outputs make it a practical choice where a flush-fitting, timber-friendly, fail-safe locking solution is needed. While it is important to confirm suitability against local safety and building codes (especially regarding fail-safe vs fail-secure requirements) and to have installation performed by a competent technician, the SB-235 is well positioned for apartment entry doors, internal office doors, light industrial applications and any situation where a discreet but robust locking device is preferred.
For accurate installation guidance, wiring diagrams, and certification details, consult the manufacturer datasheet. If you need assistance choosing between fail-safe and fail-secure devices or comparing the SB-235 to mag locks or electric strikes for a particular door and site, discuss your site requirements with a qualified access-control installer or supplier.
