Altronix PACE4KL 4-Port 10Base-T1L Single Pair Ethernet Adapter/Switch
Overview
The Altronix PACE4KL is a 4-port Single Pair Ethernet (SPE) adapter and switch designed to push IP connectivity up to 1km (3,280 ft.) over a single twisted pair — the same two-wire infrastructure that's been in buildings for decades. If you're deploying IP cameras or access control readers into existing coax or twisted-pair runs without pulling new Cat5e, the PACE4KL is the device that makes it financially viable. It bridges 10Base-T1L (IEEE 802.3cg) SPE on four ports to a standard 10/100BaseT Ethernet uplink, eliminating the need to rewire entire facilities for modern IP systems.
This isn't a product for greenfield structured cabling — it's built for retrofit and extension scenarios where rewiring is cost-prohibitive or physically impractical. The board draws just 2.5W at 12 or 24VDC input, keeps a compact footprint at 5.5" x 3.6" x 1.125", and carries UL/cUL and CE listings under UL 62368-1 for installations where agency compliance matters.
Key Features
- 1km SPE reach over 2-wire UTP: 10Base-T1L (IEEE 802.3cg) extends IP data 3,280 feet over a single twisted pair — roughly 10x the range of standard 100BaseT. That covers perimeter cameras on large campuses, parking structures, and warehouse edges without mid-run repeaters or fiber runs. Browse the full network switches and extenders category for complementary infrastructure.
- 4 SPE ports + 1 Ethernet uplink: Four field devices connect on the SPE side while a single 10/100BaseT auto-negotiating uplink carries aggregated traffic back to your switch or NVR. Half/full duplex auto-negotiation means no manual config on the uplink port.
- Daisy-chain up to 4 units: Chain four PACE4KL boards together to scale to 16 SPE endpoints on a single infrastructure leg. For long corridors or perimeter runs with multiple camera positions, this avoids running separate home-run cables back to the head end.
- 2.5W input power, 12/24VDC: At 210mA on 12V or 105mA on 24V, the board integrates cleanly into existing low-voltage power distribution — no dedicated high-current feed required. Compatible with standard Altronix power supplies already deployed in most security panels.
- –40°C to 75°C operating range: Same temperature envelope for both operating and storage means it survives unheated utility closets, outdoor enclosures, and industrial environments without derating. Most competitive gear stops at –20°C or 0°C on the cold end.
- UL 62368-1 / UL/cUL / CE listed: Carries the agency marks required for commercial and enterprise installations where AHJ approval or insurance underwriting depends on listed equipment. CE marking opens European deployments on the same SKU.
- Compact board form factor (5.5" x 3.6"): Drops into an existing enclosure alongside power supplies and control boards rather than requiring a dedicated rack space. Shipping weight of 0.75 lb. means freight cost is negligible even for multi-unit deployments.
- 85% RH operating humidity tolerance: Handles the humidity found in parking garages, loading docks, and light industrial spaces without additional environmental conditioning.
Integration & Compatibility
The PACE4KL sits at the physical layer — it converts 10Base-T1L SPE to standard 10/100BaseT Ethernet, making it protocol-agnostic. Any IP device that runs on 10/100 Ethernet (cameras, access readers, IoT sensors) connects on the uplink side of your existing switch, and any SPE-capable endpoint connects on the field side. It is not a PoE injector — field devices requiring power over the SPE link need a separate power solution. The two-wire run uses standard UTP twisted pair; shielded cable is not specified as a requirement in the evidence.
For deployments using network video recorders, the PACE4KL uplink feeds directly into any switch port the NVR sees, with no special VLAN or QoS configuration required at the SPE layer. When daisy-chaining up to 4 units, plan your uplink aggregation point to avoid creating a single-point-of-failure for an entire camera chain. Consult a surveillance system design guide for topology recommendations on multi-unit chains.
The 2-wire SPE infrastructure is also compatible with cable runs originally installed for analog systems, which is the primary retrofit use case for this device. Confirm wire gauge and run quality before committing to the full 1km distance in marginal-condition cable plants.
Frequently Asked Questions
Q: What is the maximum cable distance supported by the PACE4KL?
A: The PACE4KL supports up to 1km (3,280 ft.) per SPE segment over 2-wire twisted pair using the 10Base-T1L (IEEE 802.3cg) protocol.
Q: Can I daisy-chain multiple PACE4KL units, and how many?
A: Yes. Up to 4 PACE4KL units can be daisy-chained, allowing up to 16 SPE endpoints on a single infrastructure chain.
Q: What input voltage does the PACE4KL require?
A: The PACE4KL accepts 12VDC or 24VDC input. It draws 210mA at 12V and 105mA at 24V, consuming 2.5W total.
Q: Does the PACE4KL provide Power over SPE (PoESP) to field devices?
A: The available evidence does not confirm PoE or Power over SPE delivery to field endpoints. The board has its own DC power input; for powered field devices, verify power sourcing separately.
Q: Is the PACE4KL UL listed?
A: Yes. The PACE4KL carries UL/cUL and CE agency listings, tested under UL 62368-1.
Q: What type of cable does the PACE4KL use on the SPE side?
A: The PACE4KL uses standard 2-wire twisted pair (UTP) on the SPE ports — the same infrastructure commonly found in legacy analog camera installations.
The PACE4KL is the device I reach for when a retrofit project has existing 2-wire runs that would cost a fortune to replace. The 1km 10Base-T1L spec is the headline number, but what actually makes this board work in the field is the –40°C to 75°C operating range — I've dropped it into unheated outdoor enclosures in northern climates without losing sleep about cold-soak failures that would kill a lesser device.
Technical Highlights:
- 1km over 2-wire UTP: 10Base-T1L per IEEE 802.3cg delivers 3,280 ft. of IP reach on infrastructure that was never designed for it — 10x what you get from standard 100BaseT. That gap is what makes perimeter and parking-structure retrofits viable.
- 2.5W at 12/24VDC: Draws 210mA at 12V or 105mA at 24V. That's low enough to tap into an existing Altronix power supply without adding a dedicated power feed, which keeps installation labor down on multi-unit deployments.
- 4-unit daisy-chain: Chain four PACE4KL boards for 16 SPE endpoints on a single cable leg. On a 200-foot corridor with four camera positions, you're running one 2-wire trunk instead of four home runs.
Deployment Considerations:
- The 1km distance rating assumes reasonable cable plant condition — degraded or spliced legacy runs may not hit the full distance. Test the run first on any cable older than 15 years before committing to the topology.
- Power over SPE to field devices is not confirmed in the spec data. Budget a separate power source for any camera or reader at the far end of the SPE link.
Best fit for large-facility security upgrades — correctional facilities, university campuses, and distribution centers where existing 2-wire infrastructure runs hundreds or thousands of feet and rewiring is off the table.
