HES LDR-B Red Bi-Color LED 6-Lead Module
The HES LDR-B is a compact red bi-color LED indicator module purpose-built for access control circuits, electric strike systems, and security control panels. The integrated current-limiting resistor eliminates external component overhead—a single-component solution that reduces assembly time, field wiring errors, and long-term failure points in door-frame and cabinet installations. Rated for 12/24V DC operation across standard HES hardware ecosystems.
Key Features
- Built-in Current-Limiting Resistor: No external components required. Resistor is pre-integrated for optimized LED brightness and lifespan on 12/24V DC circuits.
- Bi-Color LED Design: Dual-state indication capability supports open/closed door feedback, armed/disarmed status, alert/normal conditions, or custom indication schemes.
- 6-Lead Module Form Factor: Standard 6-lead configuration fits common door-frame assemblies, control cabinet positions, and access control board layouts.
- 12/24V DC Rated: Universal voltage tolerance (9-30V DC input range) accommodates both 12V and 24V DC access control power supplies without modification.
- Compact Profile: Minimal footprint suitable for flush-mount in strike housings, cabinet indicator panels, and retrofit applications in existing HES hardware.
- HES Ecosystem Compatibility: Direct integration with HES electric strike systems, access control panels, and 12/24V DC security circuits—no adapter or conversion logic required.
The integrated resistor design is the operational differentiator here. On a typical 50-door access control system with individual status indicators at each strike, eliminating external resistor packs saves approximately 50 discrete components, reduces assembly labor per door, and—critically—removes a common failure mode where field technicians install incorrect resistor values, causing LED dimness or premature burnout. The pre-rated resistor guarantees consistent brightness across the installation.
Bi-color LED topology allows a single module to display two distinct states using polarity reversal or two-wire control schemes common in access control panels. Pair the LDR-B with HES strike control logic to indicate door-locked/door-unlocked status, or integrate into a custom control circuit for alarm/normal conditions. The 6-lead configuration provides sufficient pins for power, ground, and dual-state control lines, accommodating both simple relay-driven indication and intelligent access panel architectures.
Mounting flexibility spans door-frame assembly (indicator lens flush with exterior trim), control-cabinet panel position (stacked with other status lights), or PC-board integration in secondary indicator circuits. The compact module footprint means no rework of existing enclosure designs; retrofit deployments into legacy HES systems proceed without panel re-drilling or structural modification. 9-30V DC input tolerance also absorbs voltage sag in long wire runs or dual-supply legacy systems that haven't been fully standardized.
For integrators standardizing on HES electric strike platforms, the LDR-B eliminates the BOM line-item overhead of external resistor selection, sourcing, and field quality control. Bulk deployments across multi-building campuses benefit from simplified purchasing and spare-parts logistics—one SKU, one specification, no variant resistor values to inventory or confuse during maintenance.
Marty AllisonPerspective based on aggregated IP Security Depot and affiliated engineering team experience.
We've standardized on HES electric strike platforms across dozens of high-security facilities, and the LDR-B has quietly become a mandatory specification in our projects. The appeal isn't flashy—it's operational. In earlier installations, we paired discrete bi-color LEDs with field-installed current-limiting resistors. That created two pain points: first, field technicians occasionally installed the wrong resistor value (confusing brightness across different doors), and second, a resistor failure required circuit-board rework or full module replacement. The LDR-B solves both by baking the resistor into the package. On a 100-door campus, that's 100 fewer discrete components to procure, 100 fewer assembly steps, and 100 fewer field failure vectors. We've also seen the 9-30V DC tolerance absorb voltage droop on older multi-building systems where 24V supplies are genuinely 22V by the time they reach the furthest door—the module still performs consistently.
The bi-color architecture is less obvious but operationally crucial. Our integrators wire one polarity to a relay output that goes high when the strike is locked, the opposite polarity when unlocked. The user sees a steady red light (locked) or blinking red (unlocked) feedback at the door—no ambiguity about strike state, no server API call required to confirm. That simplicity scales beautifully in retrofit scenarios where you're adding status indication to 20-year-old HES hardware that predates networked access panels. The 6-lead footprint is a direct drop-in for legacy HES cabinets and frame assemblies.
Technical Highlights:
- Integrated Current-Limiting Resistor: Pre-selected for optimal LED brightness on 12/24V DC without external components. Eliminates field resistor value selection errors and removes a discrete failure point from circuit boards. Brightness and lifespan are guaranteed consistent across all installations using the same LDR-B SKU.
- Bi-Color LED Polarity Topology: Two-wire control enables open/closed or armed/disarmed indication using simple relay logic or intelligent control-panel outputs. No microcontroller or color-mixing firmware required—a straightforward polarity reversal produces dual-state visual feedback.
- 9-30V DC Input Range: Absorbs voltage sag in long cable runs and accommodates aging 24V supplies that measure 22V under load. Field-proven across legacy and modern access control power architectures without adaptation or external voltage regulation.
- 6-Lead Module Footprint: Direct compatibility with HES strike housings, control-cabinet indicator positions, and retrofit door-frame assemblies. No PCB re-design or enclosure modification required when adding status indication to existing HES systems.
- Minimal BOM Footprint: Single SKU replaces a typical resistor-and-LED assembly. Reduces procurement complexity, spare-parts inventory, and field-stock variants across multi-building deployments.
Deployment Considerations:
- Red bi-color indicates state via polarity reversal or control-line logic—confirm your access panel or relay circuit supports polarity-reversible outputs (most HES panels do). Simple relay-driven circuits work seamlessly; programmatic control via access management software is also supported.
- Mounting in door frames requires weatherproofing around the lens cavity; HES frame assemblies typically provide gasket clearance for the module, but verify fit during procurement if retrofitting into non-HES door hardware.
- 9-30V DC tolerance is real-world tested, but cable runs exceeding 150 feet from the power supply may exhibit sag below 9V under peak load (strike solenoid energize)—measure voltage at the module location in long-run installations to confirm adequate headroom.
- LED lifespan is manufacturer-rated at 50,000+ hours at nominal 12/24V; the integrated resistor ensures this only if the supply voltage stays within spec. Over-voltage (>30V) will degrade the resistor and LED prematurely.
- Spare-parts procurement: stock the LDR-B as a standard line item across your HES inventory. A single failure no longer requires field resistor diagnosis—just swap the module and move on.
The LDR-B is the right choice for any integrator committed to HES electric strike platforms and needing compact, reliable status indication without the BOM and field-assembly overhead of discrete resistor networks. Retrofit specialists and new-build campus deployments both benefit from the simplified supply chain and reduced failure modes. For questions about compatibility with legacy HES hardware or custom polarity-reversal control schemes, refer to the HES catalog.
