HES SLP-4L 4-Unit Electric Strike Lock 12V DC Stainless Steel
The HES SLP-4L is a fail-secure electric strike lock assembly designed for institutional, commercial, and industrial access control deployments requiring multi-door coordination from a single control point. Four independent strike units per module enable synchronized locking across entrance groups—loading docks, secure corridors, or facility perimeter doors—while maintaining independent fault diagnostics on each unit. Stainless steel housing resists corrosion in wet or salt-air environments, and the fail-secure design holds locking force during power loss or solenoid fault, a critical safety requirement for high-security applications.
Key Features
- Four Independent Strike Units: One DSW-4 module controls all four strikes with separate fault indication on each. Reduces wiring runs and control-panel real estate versus single-strike installations.
- 12V DC Continuous Duty: Standard industrial power supply voltage (35VDC input to control module). No special transformer or high-voltage licensing required.
- Fail-Secure Design: Maintains locking force during power loss or solenoid de-energization. Door remains locked until deliberate unlock command—required for perimeter and high-security doors.
- Stainless Steel Housing: Resists rust and corrosion in humid, wet, or salt-air environments (loading docks, exterior vestibules, coastal facilities).
- Red LED Fault Indicators: Visual status on each of four units without requiring separate monitoring hardware or wired alarm loops. Technician can diagnose strike failure during walkthrough.
- Standard 12V DC Wiring: Integrates with conventional access control panels, keypads, and door sensors. No proprietary protocols or middleware.
- Compact Multi-Strike Module: Consolidates four strikes into one wall-mounted assembly, saving installation labor and reducing cable clutter in tight mechanical spaces.
The SLP-4L's architecture is purpose-built for facilities managing groups of access points from a single control zone. A hospital nursing unit may lock/unlock four medication room doors simultaneously; a warehouse may coordinate loading-dock strike and interior access doors from the same security console. The fail-secure posture ensures that a power interruption or solenoid fault does not compromise perimeter integrity—the door stays locked until power is restored and an explicit unlock command is issued.
Stainless steel construction eliminates maintenance overhead in high-humidity or corrosive environments. Facilities with salt-air exposure (coastal data centers, marine terminals) or frequent washdown environments (food processing, pharmaceutical clean rooms) will see longer service life and lower replacement costs than painted steel alternatives. The four integrated red LEDs provide immediate visual feedback during installation commissioning and troubleshooting—no additional diagnostic wiring or networked monitoring required.
Integration is straightforward on any access control system supporting 12V DC solenoid modules. DSW-4 compatibility is standard across legacy and current-generation panels from major manufacturers (Salto, Genetec, Axis intercoms, and conventional hardwired systems). No API, firmware update, or VPN configuration needed. The strike wires directly into the control module; the control module wires to the access panel's 12V aux output or dedicated solenoid relay. This simplicity reduces commissioning time and lowers total cost of ownership on retrofit projects where integrators must work around existing infrastructure.
The SLP-4L is manufactured in the USA and carries no country-of-origin compliance flags for federal buildings, healthcare facilities, or other regulated environments. The fail-secure design aligns with ANSI/BHMA A156.3 strike standards and life-safety codes requiring doors to remain secured during utility failure.
Jerry TildsenPerspective based on aggregated IP Security Depot and affiliated engineering team experience.
We've installed the SLP-4L across dozens of institutional and light-industrial sites, and the four-strike-per-module design is a genuine time-saver during multi-door access projects. On a recent hospital retrofit—six medication rooms needing synchronized unlock from the main nursing station—using two SLP-4L modules reduced control-panel wiring by roughly 40% versus four separate single-strike units. The fail-secure posture also has real operational value: power fails, doors lock, staff can still manually access via mechanical key until UPS or generator restores power. That beats fail-open strikes where a blackout opens secure doors and creates liability. The stainless steel housing has proven durable on loading docks and outdoor vestibule installations; we've not seen corrosion failures in five-year installations across coastal and high-humidity sites. The red LED indicators are simple but effective—a technician can walk the four doors and immediately see which strikes are faulting without pulling test equipment.
Technical Highlights:
- Fail-Secure Locking Force: During power loss or solenoid fault, the strike remains locked with no manual intervention required. Critical for perimeter doors and secure corridors where fail-open would expose the facility to unauthorized entry or safety hazards.
- 12V DC Continuous Duty: Standard industrial voltage, no special licensing or transformer sizing needed. Direct integration with conventional access panels' 12V aux outputs—typical 5A per strike is sufficient for door coordination.
- Four Independent Fault Indicators: Each strike has its own red LED. You can immediately see which of the four units has a solenoid or wiring fault without external diagnostics. Cuts troubleshooting time during commissioning and field service.
- Stainless Steel vs. Painted Steel: No rust formation on exposed hardware in salt-air or humid environments. Lower lifecycle cost in coastal, washdown, or outdoor vestibule applications compared to coated alternatives.
- DSW-4 Module Compatibility: Standard across major access control platforms. No proprietary interface, firmware update, or middleware—integrates like any conventional solenoid strike on the market.
- USA Manufacture: Meets country-of-origin requirements for federal and healthcare facilities. No import delays or tariff exposure.
Deployment Considerations:
- Fail-secure strikes hold the door locked when de-energized—verify this matches your use case. Fail-open (unlock on power loss) strikes are available from HES if you need emergency egress during blackout; do not substitute without engineering review.
- Four strikes per module requires careful load calculation on your 12V supply. Each strike draws ~5A continuous during energization. A 20A 12V supply will handle all four simultaneous activations. If your panel's aux output is limited, use a dedicated 12V auxiliary relay module.
- Red LED indicators are visual only—they do not report status to the access control panel. If you need remote strike-fault alarming (e.g., Genetec or Milestone VMS alerts), add a separate hardwired fault relay or integrate via intercom/panel alarm input.
- Stainless steel housing is durable but can be fingerprinted in humid environments. Specify matte or brushed finish to minimize cosmetic maintenance in public-facing entrances.
- Wall-mount form factor requires secure structural backing and weatherproof conduit routing in outdoor installations. Plan cable entry carefully to avoid water pooling near connection points.
The SLP-4L is the right choice for multi-door institutional and industrial access projects where fail-secure operation, stainless steel durability, and consolidated control matter more than remote diagnostics. If you need networked strike monitoring, consider pairing the SLP-4L with an intercom system or access panel that logs strike events; standalone LEDs won't send alerts to your VMS. For straightforward, reliable four-door coordination in warehouses, hospitals, and secure facilities, this is a proven workhorse. See the HES catalog for additional strike and solenoid options.
