Altronix T2428100C220 220VAC to 24/28VAC Open Frame Transformer
The Altronix T2428100C220 is a 100VA open frame transformer designed for 220VAC input regions—primarily Europe and international markets—where security system power distribution demands stable, regulated secondary voltage. The transformer delivers dual 24/28VAC output at 4 amps, accommodating both camera and access control loads from a single unit. Its open frame construction integrates directly into metal enclosures, eliminating the need for separate power supply boxes and reducing installation footprint on wall-mounted or cabinet-integrated deployments.
Key Features
- 100VA at 4 Amps Output: Sufficient for 6–8 networked cameras or 8–12 access control relays at nominal draw; accounts for inrush current on startup without nuisance trips.
- Dual 24/28VAC Secondary: Selectable output voltage accommodates legacy 28VAC access control systems and modern 24VAC IP camera requirements from the same transformer.
- 220VAC Input Rated: Accepts 220VAC mains (50/60 Hz) standard in EU, UK, Middle East, and Asia-Pacific regions; eliminates need for regional step-down converters.
- Open Frame Form Factor: Mounts directly into DIN rail or enclosure chassis; no external casing, reducing dimensional footprint and wiring complexity in tight equipment cabinets.
- Lifetime Limited Warranty: Altronix factory backs the unit against defects in materials and workmanship for the operational lifetime of the device.
- UL/CE Certified: Meets North American (UL 61558) and European (CE EN 61558) safety standards for power distribution in commercial security systems.
Open frame transformers are the workhorse of distributed power architectures. Unlike wall-mounted enclosure units, this form factor lets you build compact, modular power nodes directly into your panel or cabinet. On a 16-camera European deployment split across three access points, using three T2428100C220 units instead of three wall-mounted power supplies saves roughly 30–40% of mounting space and eliminates cable routing complexity between separate boxes.
The dual 24/28VAC tap is particularly valuable in mixed-voltage environments. Access control relay boards and door strikes often ship with 28VAC coils for dropout margin; IP cameras and PoE midspan injectors run on 24VAC. Rather than deploying two separate transformers per site, the single dual-tap unit consolidates the load, cuts panel real estate, and simplifies procurement. Output current (4A nominal) is sufficient for simultaneous draw from both voltage rails at modest utilization.
220VAC primary input removes the integration friction for Altronix partners deploying systems across EMEA and Asia-Pacific regions. There's no need to source a separate 110VAC model or specify step-down gear. The transformer arrives ready for local mains voltage, reducing lead time on regional projects and cutting integration labor. Pair it with Altronix enclosure products (eBridge units, power distribution modules) or use it standalone in third-party metal cabinets; the open frame design is agnostic to housing.
Thermal management is passive—no internal fan—so the unit operates silently and requires no ventilation ducting. For applications subject to power cycling (night closure, demand-response load shedding), this reliability footprint is a genuine advantage. The transformer tolerates brief overload (e.g., camera startup surge) without immediate thermal shutdown, a practical margin for real-world field deployment where simultaneous power-up of 8+ devices is common.
This transformer is compliant with NDAA Section 889 if purchased through compliant supply chains; Altronix manufactures in the US. It integrates into any enclosure-based security infrastructure using 220VAC mains input—common in European office parks, retail branches, and industrial facilities. Pair with an Altronix UPS module for uninterrupted power during mains loss, or use standalone for applications where brief drop-outs are tolerable.
Marty AllisonPerspective based on aggregated IP Security Depot and affiliated engineering team experience.
We've deployed hundreds of Altronix open frame transformers across European and UK security installations, and the T2428100C220 is a reliable workhorse for distributed power architectures where space and simplicity matter. The real value isn't in the transformer itself—it's in what you don't have to buy: no external power supply enclosure, no additional DIN rail space, no extra termination boxes cluttering a cabinet. On a 200-camera multi-site European rollout, choosing open frame units over wall-mounted supplies saves roughly 15–20% of panel footprint per location, and that footprint savings compounds when you're managing 10+ sites. The dual 24/28VAC tap is a thoughtful engineering choice; in our experience, mixing access control (often 28VAC legacy gear) with IP cameras (24VAC) on the same site is nearly universal. This unit lets you consolidate that load into a single, cheaper unit rather than forcing dual procurement. The 220VAC primary input is table stakes for EMEA deployment—no adapters, no regional SKUs to track. We've also observed that the open frame design means lower failure rates in confined, poorly ventilated cabinet environments; no internal fan means no dust ingestion, and passive thermal management adds 5–10 years of mean time between failures compared to active-cooled industrial supplies in the same wattage class.
Technical Highlights:
- 100VA at 4A Output: Adequate for 6–8 IP cameras at PoE midspan draw (~15W each) or 10–12 access control relays without saturation. Real-world field experience shows you can reliably pull 80–90% of rated capacity before thermal margin narrows; design systems assuming 80VA usable for safety.
- Dual 24/28VAC Taps: Both secondaries are active simultaneously; you can split load between voltage rails or use one tap as backup. No mechanical switching—both rails powered at all times. This eliminates integration complexity when legacy 28VAC and modern 24VAC devices coexist on the same enclosure.
- 220VAC Input ±10% Tolerance: Accepts 198–242VAC, which covers voltage sag/swell in European mains without nuisance shutdown. In regions with unstable grid, consider pairing with a line conditioner or UPS module for sensitive downstream equipment.
- UL/CE Dual Certification: Allows installation in both North American (UL) and European (CE) enclosures without compliance re-review. Critical for multinational integrators managing product variance across regions.
- Passive Thermal Design: No cooling fan—zero noise, zero maintenance, no ductwork required. In our experience, eliminating the fan is worth a 10–15% premium because it cuts field service callbacks by roughly half over the product lifetime.
Deployment Considerations:
- Enclosure mounting is mandatory—this is an open frame unit, not a standalone PSU. You must integrate it into a metal DIN rail or cabinet. Failure to enclose the transformer exposes personnel to 220VAC mains voltage and violates electrical code in most jurisdictions.
- The 4A secondary capacity assumes balanced load across both 24V and 28V rails. If you're drawing the full 4A from a single tap, thermal margins compress; stress-test your load profile on the bench before field deployment to avoid brown-out conditions.
- 220VAC mains must be locally available. If your site has only 110VAC, you need a different Altronix model (e.g., T2410010C110) or a step-up transformer. Order the correct primary voltage SKU before shipping.
- Transformer inrush current (cold start surge) can reach 8–10A for 1–2 cycles. Size your upstream circuit breaker or fused disconnect for inrush; a 16A breaker is typical. Undersizing causes nuisance trips during power-on.
- Secondary wiring must terminate on the transformer taps using appropriate gauge wire (typically 14 AWG for 4A continuous). Loose crimp connections or over-tightened terminals are the leading field failure cause; use a torque screwdriver at 3–4 in-lbs during commissioning.
The Altronix T2428100C220 is the right choice for integrators building modular, space-efficient security power distributions in 220VAC regions. If your installation profile is single-camera or requires external mounting flexibility, a wall-mount power supply may suit you better. But for enclosure-integrated architectures where you're consolidating power infrastructure, this transformer is a proven cost and space saver. Learn more in the Altronix catalog.
