Altronix SMP5PMP8 Dual 12VDC Supervised Power Supply/Charger
The Altronix SMP5PMP8 is a compact supervised power supply and battery charger engineered for access control and security systems that require redundant 12VDC distribution with integrated backup charging. This eight-output unit accepts 16–28VAC input and delivers dual independent 12VDC rails, each supporting loads up to 6A per channel. The SMP5PMP8 integrates battery backup supervision directly into the power distribution architecture, eliminating the need for separate battery chargers in mid-scale distributed security deployments.
Key Features
- Eight independent 12VDC output channels: Provides granular power distribution across eight separate loads without a single point of failure. Each channel can source 0.5A, 4A, or 6A depending on your load requirements — important when mixing low-draw sensors with higher-draw devices like access control readers or camera encoders on the same supply.
- Dual independent 12VDC rails: Two isolated output groups allow you to segregate critical loads (door strikes, readers) from less critical auxiliary circuits (LED indicators, buzzers). If one rail experiences an overload, the other continues to supply power.
- Integrated battery charger with backup supervision: Built-in charging logic handles 12VDC backup batteries without requiring a separate charger module. Reduces physical footprint and simplifies installation — one unit handles power distribution and emergency backup charging in a single enclosure.
- AC Fail, Low Battery, and Battery Presence monitoring: Three dedicated supervision channels report system status to your access control panel or security management platform. AC Fail alerts you immediately when mains power is lost; Low Battery triggers before your backup is depleted; Battery Presence confirms the backup is connected. Prevents silent failures in unattended locations.
- 16–28VAC input range: Accepts transformer outputs across a wide window, useful when power sources vary slightly or when you need to share a single transformer across multiple sites. No voltage regulation module required for input swings in this range.
- Compact 7″L × 4″W × 1″H form factor: Mounts directly inside access control enclosures or small cabinet spaces without consuming an entire DIN rail or dedicated shelf. Ideal for retrofit installations where panel real estate is already constrained.
- CE approval for European deployments: Meets European electromagnetic compatibility (EMC) and electrical safety directives, streamlining installations across EU jurisdictions and reducing compliance paperwork.
- Lifetime Limited Warranty: Manufacturer stands behind the product for the life of ownership under normal operating conditions — a signal of confidence in component selection and manufacturing process.
Integration & Compatibility
The SMP5PMP8 works with any 12VDC powered access control device: magnetic locks, electric strikes, credential readers, exit devices, and alarm control panel auxiliaries. The three supervision outputs (AC Fail, Low Battery, Battery Presence) connect to digital inputs on your panel or directly to a monitoring station. If you're deploying distributed power across multiple security integration points, the dual-rail topology lets you group related doors or zones on separate channels, reducing risk of a single failed device power-cycling an entire zone.
When to Choose a Different Model
If you need 24VDC outputs instead of 12VDC, consult the full Altronix supervised power supply catalog for a 24VDC variant. If your AC input is unstable, metered, or subject to frequent brownouts, consider a UPS-grade supply with active power factor correction. If you need more than eight outputs, look for larger frame sizes in the same SMP family.
Frequently Asked Questions
Q: Can I use the SMP5PMP8 to back up multiple doors simultaneously?
A: Yes. Each of the eight 12VDC outputs can drive a separate backup battery (or a subset of outputs can share a single larger battery). The integrated charger monitors the battery voltage and charges as long as AC mains are present. If AC fails, all charged batteries begin discharging to power their assigned loads.
Q: What size backup battery should I use with the SMP5PMP8?
A: That depends on your load current and required backup runtime. The SMP5PMP8 datasheet specifies safe charging profiles; multiply your estimated load current by desired runtime (in hours) to find Amp-hour capacity. A typical single-door access control system with an electric strike might require a 12Ah battery for 8–12 hours of backup. Consult your system designer or battery supplier.
Q: Does the SMP5PMP8 support 24VAC input, or only 16–28VAC?
A: The unit accepts 16–28VAC input, so standard 24VAC transformer outputs (typically ±10% tolerance, 21.6–26.4VAC) fall well within this window. You can safely connect a 24VAC transformer directly without conditioning.
Q: What does the AC Fail supervision output do?
A: The AC Fail contact closes (or opens, depending on polarity wiring) when mains AC power is lost. Connect this to your access control panel's power loss input to trigger alarm events, unlock doors for emergency egress, or send notifications to your monitoring center. It acts as an early warning before backup batteries begin to drain.
Q: Is the SMP5PMP8 suitable for outdoor installations?
A: No. The SMP5PMP8 is rated for indoor use only. If you need supervised power in outdoor or wet environments, you'll require an enclosure-rated supply with IP67 or higher ratings. Always mount the SMP5PMP8 inside a weatherproof cabinet or access control enclosure.
Q: Can I daisy-chain multiple SMP5PMP8 units for higher current?
A: No. Do not parallel the outputs of multiple SMP5PMP8 units — each unit is designed as a standalone supervised supply. If you need more than 48A total capacity (8 outputs × 6A), install additional SMP5PMP8 units on separate AC feeds and distribute your loads accordingly, or consult a larger Altronix frame for higher aggregate capacity.
Ted PerryPerspective based on aggregated IP Security Depot and affiliated engineering team experience.
The Altronix SMP5PMP8 is a workhorse for any mid-scale access control deployment where you need both power distribution and battery backup in a single compact unit. The eight-output architecture with dual independent rails is the real value here — it gives you flexibility to group related loads and isolate faults without forcing a redesign of your control panel wiring.
Technical Highlights:
- 6A per output at 12VDC: Adequate for one electric strike or two credential readers per channel without needing additional buffers or relay modules. If you push beyond 6A on a single output, you'll trigger overcurrent protection and drop that channel — a safety feature, not a limitation, but one to account for during capacity planning.
- Dual independent rails with isolated supervision: Each rail can run its own backup battery. If one battery fails or is depleted, the other rail continues charging and powering its loads. AC Fail, Low Battery, and Battery Presence contacts give your control panel real-time visibility into power health — not a luxury in unattended locations.
- 16–28VAC input range: Wide tolerance for transformer variation means you're not locked into a single supplier or transformer brand. Transformers age and can drift; this unit absorbs that drift without regulation issues. In retrofit work, this flexibility often saves a whole transformer swap.
Deployment Considerations:
- The SMP5PMP8 must live inside an enclosure — it's not weather-sealed and will fail if exposed to humidity or temperature swings beyond typical indoor HVAC limits. Always mount it in an access control cabinet or secured panel space.
- Battery charger is 'smart' but not configurable — it assumes standard lead-acid or AGM chemistry. If you want to use lithium or specialized batteries, consult Altronix support for compatibility before purchase.
- Eight outputs sounds like plenty until you start distributing; a typical 8-door system uses all eight channels. Plan for future expansion early — adding capacity later means swapping the whole supply, not just adding a module.
This unit is purpose-built for the classic access control retrofit: old analog lock systems moving to networked readers, older panels needing a 12VDC boost without a full panel replacement. If you're installing new systems, Altronix's larger supervised supplies or PoE-powered readers might reduce wiring, but the SMP5PMP8 remains the standard answer for 12VDC backup in small-to-medium multi-door deployments.
