Middle Atlantic PDX-920R 9-Outlet 20A Rack Power Distribution Unit
Overview
The Middle Atlantic PDX-920R is a 1U rack-mount power distribution unit from the NEXSYS series — built for AV integrators and security installers who need dependable, protected power across up to nine devices in a single rack space. Rated at 20A input with nine NEMA 5-20R outlets, the PDX-920R handles real-world mixed loads across cameras, recorders, network switches, and encoders without requiring a separate outlet strip or unprotected power block.
Middle Atlantic is a recognized name in rack power distribution for commercial AV and security infrastructure, and the NEXSYS series reflects that pedigree — practical, properly spec'd, and sized for 1U rack bays.
Key Features
- Nine NEMA 5-20R Outlets at 20A Input: Nine individually accessible outlets on a 20A circuit means you can feed an NVR, PoE switch, a few encoders, and still have spare capacity. The 20A input accommodates higher-draw equipment that trips standard 15A strips — important if your rack includes server-grade hardware or high-port-count PoE switches drawing significant idle wattage.
- 16A Rated Load: The PDX-920R's 16A rated continuous load (80% of the 20A breaker) follows the NEC 80% continuous load rule by design. Plan your outlet loading around 16A maximum to stay within spec — don't fill all nine outlets to capacity and assume 20A is available continuously.
- 705-Joule Multi-Stage Surge Protection: At 705 joules, this unit absorbs transient spikes that would otherwise reach sensitive electronics — NVR motherboards, switch ASICs, and camera power inputs are all vulnerable to power line transients. Multi-stage topology means the surge is clamped at more than one point in the circuit rather than a single MOV, which degrades faster under repeated smaller surges.
- Sub-Nanosecond Response Time: The surge response triggers in less than 1 nanosecond — faster than virtually any transient can damage a semiconductor junction. This isn't marketing language; it reflects the physics of the clamping components used. A unit that responds in microseconds can still allow damaging voltage through before the clamp engages.
- 80–140VAC Voltage Range: The PDX-920R accepts input from 80 to 140VAC, which covers brownout conditions down to roughly 33% below nominal and overvoltage up to 17% above. In facilities with known voltage sag issues — older buildings, generator-backed panels that surge on transfer — this range keeps equipment running where a narrower-tolerance unit would drop offline.
- 1U Rack Form Factor (19 × 1.75 × 8.75 in): Standard 19-inch, 1U profile mounts in any EIA-standard rack without adapter rails. The 8.75-inch depth fits shallow 12-inch-deep relay racks and wall-mount enclosures, not just full-depth server cabinets — relevant if you're building compact security or AV head-end closets.
- 60 Hz / 120VAC Input: North American power standard only. Confirm before deploying in facilities with international power infrastructure or generator outputs configured for non-standard frequencies.
Integration and Compatibility
The PDX-920R fits any EIA-standard 19-inch rack — open-frame, enclosed, and wall-mount configurations. Nine NEMA 5-20R outlets are compatible with standard North American power cords on NVRs, managed switches, rack-mount servers, and AV processing equipment. The PDX-920R pairs naturally with rack-mount network video recorders and PoE network switches that anchor most security system head-ends.
If your deployment requires battery backup in addition to surge protection, the PDX-920R is a distribution layer — pair it downstream of a UPS on the same circuit for both runtime protection and surge clamping. The PDX-920R handles distribution and surge; the UPS handles runtime and voltage regulation.
For larger deployments requiring more outlets or higher joule ratings, review the broader Middle Atlantic power and rack catalog for NEXSYS variants with expanded outlet counts or 30A input options. Consult a rack power planning guide to calculate actual load requirements before specifying outlet count and amperage.
Frequently Asked Questions
Q: What is the maximum continuous load for the PDX-920R?
A: The PDX-920R has a 20A input, but the rated continuous load is 16A — in line with the NEC 80% continuous load rule. Do not plan deployments that rely on sustained draw above 16A across all nine outlets.
Q: How many joules of surge protection does the PDX-920R provide?
A: The PDX-920R provides 705 joules of multi-stage surge protection with a response time of less than 1 nanosecond.
Q: Will the PDX-920R work during a brownout or voltage sag?
A: Yes. The PDX-920R accepts input voltages from 80 to 140VAC, which means it continues operating during voltage sags down to roughly 80V — common in aging facilities or on generator-backed panels during transfer events.
Q: Can the PDX-920R mount in a shallow wall-mount rack enclosure?
A: The PDX-920R measures 19 inches wide × 1.75 inches high × 8.75 inches deep. At under 9 inches deep, it fits in shallow 12-inch-depth wall-mount enclosures that would reject full-depth 1U PDUs.
Q: What outlet type does the PDX-920R use?
A: All nine outlets are NEMA 5-20R — standard North American 20A receptacles compatible with NEMA 5-20P plugs (which includes most rack-mount NVRs, switches, and AV equipment using standard North American power cords).
Q: Does the PDX-920R include battery backup?
A: No. The PDX-920R provides surge protection and power distribution only — it does not include a battery or UPS function. For runtime protection, deploy it downstream of a separate UPS.
The spec I always check first on a PDU is joule rating relative to outlet count — and the PDX-920R lands at 705 joules across nine NEMA 5-20R outlets, which is a solid ratio for a head-end rack running mixed security loads. I've seen 200-joule strips on racks with $8,000 NVRs sitting on them, and that's just asking for a service call after the next utility transient. The PDX-920R (often searched as PDX 920R) is priced and sized for installations where the integrator actually thought about what's downstream.
Technical Highlights:
- Multi-Stage Surge at 705 Joules: Multi-stage topology distributes clamping across more than one circuit stage — a single MOV at 705J degrades faster under repeated smaller surges than a staged design does. Longer effective life before the protection element is spent.
- Sub-Nanosecond Response: Less than 1 nanosecond response means the clamp engages before a fast transient — the kind generated by lightning coupling or capacitor bank switching on a shared utility feed — can reach a semiconductor junction. Microsecond-class strips are measurably slower by four orders of magnitude.
- 16A Rated / 20A Input: The 16A continuous rating built into this unit effectively enforces the NEC 80% rule without the integrator having to calculate it. If you're loading a rack with a high-port-count PoE switch (potentially 12–15A at full load) plus an NVR and a few encoders, run the numbers against 16A, not 20A.
Deployment Considerations:
- At 8.75 inches deep, the PDX-920R fits 12-inch-depth wall-mount enclosures — but confirm your specific enclosure's usable interior depth after accounting for door clearance and cable management before specifying.
- The 80–140VAC input range handles generator transfer sags, but this is not a voltage regulator. If the site has chronic over/undervoltage outside that 80–140V window, a line-interactive UPS upstream is the right fix — the PDX-920R won't compensate for that.
This unit is the right call for a compact security head-end in a retail, school, or municipal building where you have one 20A circuit feeding the rack and need protected distribution across an NVR, a managed PoE switch, and auxiliary gear — all in a single 1U bay.
