Hikvision DS-K4H250S Single-Door Electromagnetic Lock Controller
Overview
The Hikvision DS-K4H250S is an electromagnetic lock controller engineered for single-door access control in commercial, institutional, and high-security environments. With a maximum holding force of 272 kg (599.8 lb) of linear thrust, this unit delivers the mechanical security required for warehouse entry points, data center access, healthcare facilities, and corporate office perimeter doors. The DS-K4H250S integrates directly with Hikvision access control systems and third-party controllers via dry contact relay outputs, eliminating the need for standalone magnetic lock modules and reducing integration complexity on your control panel.
Key Features
- 272 kg (599.8 lb) holding force: Sufficient to secure single-leaf, double-leaf, wooden, glass, metal, and fireproof doors without supplemental mechanical locks. This is a genuine threshold spec—if your load calculations exceed 272 kg, you'll need a higher-capacity model or a dual-lock arrangement.
- Dual voltage operation (12 VDC/500 mA or 24 VDC/250 mA): Choose based on your available power infrastructure. The 24 VDC mode draws half the current, reducing strain on power supplies in multi-door installations. Both modes are field-selectable, so you can adapt to existing cabinet voltage without hardware replacement.
- Dry contact relay outputs (3A maximum): NO (normally open when locking) and NC (normally closed when unlocking) outputs allow integration with external alarm systems, door sensors, or supplemental locks. The 3A rating supports standard electromagnetic strikes and indicator lamps but cannot drive high-current solenoids directly.
- Status indicator LEDs (green/red): Green indicates lock engaged; red indicates unlocked. Useful for local verification during installation and troubleshooting, though integration with your access control system's event log is the authoritative status source.
- Operating temperature range -10°C to 55°C (14°F to 131°F): Covers unheated loading docks, warehouse receiving areas, and outdoor sheltered enclosures. Humidity tolerance up to 95% RH prevents corrosion on the lock body and armature in humid climates—standard for coastal facilities or high-moisture industrial spaces.
- Compact form factor (240 × 49 × 25.5 mm; 2.1 kg): Minimal depth and weight simplify mounting on single-door frames without frame modification. Fits standard North American and European door strike templates.
- Eco-friendly zinc alloy construction with electroplating: Lock body and armature plate feature zinc coating; shell uses hard anodized electroplating. This combination resists surface corrosion in non-salt-spray environments. If salt-fog exposure is a factor (coastal marine installations), specify stainless steel variants available in the magnetic lock family.
Integration and Compatibility
The DS-K4H250S ships as a standalone electromagnetic lock with integrated relay outputs. It pairs with Hikvision access control panels (DS-K2000 series, DS-K3000 series) and any third-party controller that can supply 12 VDC or 24 VDC and manage relay switching via a standard access control reader or proximity card system. The dry contact outputs are non-isolated—ensure your control panel output circuits are properly rated for 3A maximum current to avoid relay chatter or circuit damage. For multi-door installations, consult the access control system planning guide to calculate total current draw and verify your power supply capacity.
Typical Applications
- Single warehouse entry points with badge or PIN-based access
- Server room and data center access control
- Hospital staff-only areas and medication storage
- Government building perimeter and secure room entry
- Corporate office after-hours access control
- Multi-tenant commercial space tenant-specific doors
Frequently Asked Questions
Q: Can the DS-K4H250S hold a double-leaf (double-door) entry?
A: Yes—the 272 kg holding force is sufficient for double-leaf doors in most commercial applications. However, each leaf increases the pull force required to break the magnetic bond. Verify that your specific door hardware and frame design stay within the 272 kg limit. If in doubt, consult your access control integrator or test the door force on-site before final commissioning.
Q: What happens to the lock if power is lost?
A: The DS-K4H250S is a fail-safe electromagnetic lock—it releases (unlocks) when power is interrupted. This is by design: the magnetic field holding the armature plate in place collapses, allowing the door to open. This behavior is appropriate for normal fire egress requirements but unsuitable for high-security detention or secure vault applications. For fail-secure (remains locked on power loss) behavior, you'll need a different lock type or a dedicated battery backup for this unit.
Q: Can I use the DS-K4H250S on a glass door?
A: Yes. The lock mounts on the door frame (jamb), not the glass pane itself. Glass door compatibility depends on the frame material (wood, aluminum, metal). Ensure the frame has a suitable mounting surface and that the strike plate has adequate contact with the armature. For full-glass frameless doors, consult your integrator—additional brackets or hardware may be required.
Q: Does the DS-K4H250S require a separate power supply?
A: No external PSU is required if your access control panel or a centralized power module already supplies 12 VDC or 24 VDC. The lock draws 500 mA @ 12 VDC or 250 mA @ 24 VDC, so verify that your control panel's output circuit(s) can source that current. For installations with multiple locks, a dedicated 24 VDC power supply feeding all locks reduces panel load and improves reliability.
Q: Is the DS-K4H250S suitable for outdoor use?
A: The unit operates at -10–55°C and tolerates 95% RH, making it suitable for covered outdoor entries, loading dock access, and sheltered exterior doors. However, it is not rated for direct rain exposure without an enclosure. If the lock body will be exposed to weather, install it within a weatherproof junction box or select a stainless-steel variant designed for coastal or high-humidity salt-spray environments.
Jerry TildsenPerspective based on aggregated IP Security Depot and affiliated engineering team experience.
I've integrated dozens of single-door access control systems, and the DS-K4H250S (often searched as DS K4H250S) remains a workhorse for mid-security warehouse and office deployments. The 272 kg holding force sits at a sweet spot—strong enough to deter casual bypass attempts without requiring overbuilt door frames—and the dual voltage flexibility saves you from designing separate power trees for different facility zones.
Technical Highlights:
- Holding force (272 kg): Roughly equivalent to a 600 lb pull. This assumes a single-point strike mounting; if your door hardware allows the armature to twist or pivot, effective holding force drops. Always verify contact geometry on-site.
- Dual voltage (12/24 VDC) with field-selectable mode: Avoids the cost and lead time of stocking two SKUs. The 24 VDC mode cuts current draw in half—critical in installations where you're running dozens of locks off a single 48 VDC power module.
- Relay outputs (3A max, NO/NC): The NO contact fires when the lock engages (locked state); NC fires when released. Standard relay logic, but the 3A ceiling means you cannot drive a second heavy solenoid from the same relay without an external contactor.
Deployment Considerations:
- Fail-safe behavior on power loss is appropriate for life-safety egress but wrong for high-security vaults or detention. If your spec requires fail-secure, reject this model outright and specify a latch-bolt lock with a solenoid strike instead.
- The zinc alloy body is adequate for dry indoor environments and covered outdoor areas. Salt-spray and continuous high humidity (>95% RH) will corrode plating within 18–24 months—if you're on the coast or in a food processing facility, step up to stainless steel variants in the same family.
The DS-K4H250S is the right choice for warehouse receiving areas, office after-hours badge access, and lab entry where you need straightforward fail-safe behavior and don't want to over-engineer the infrastructure. Avoid it for detention facilities, cash rooms, and high-moisture salt-spray environments where it will fail prematurely.
