zPDS

The Zonit Data Center Power Distribution System (zPDS™) delivers an ultra-reliable, turnkey power distribution system for modern high-availability mission-critical data centers. It simplifies the distribution, phase balancing and delivery of power between data center Power Panels or Busways and end-user racks, cages and servers. It enables quick and easy changes to power distribution at the rack while eliminating the need to de-energize power panels, busways and/or power whips. It reduces the domain of power outages when branch circuits are overloaded and trip circuit breakers. It eliminates many sources of errors that result in downtime and unbalanced use of power phases. It is compatible with all standard power distribution methods: traditional whips, busways and flexible metallic sealed or unsealed modular whips. It can be reconfigured by data center staff, it does not require electricians for reconfiguration.

Technically the Zonit zPDS System offers unique patented functionality, high power density, complete power redundancy and unmatched reliability backed by a long-term warranty.

De-Energized Power Configuration Changes

zPDS is an Ideal Solution for De-energized Changes in the Data Center. The Zonit zPDS System enables electrical adds, changes and moves without the need to have an electrician provide the service due to the unique flexibility of the system.  Plug adapters and per hot-feed fast circuit breakers provide a highly reliable, yet very adaptable power delivery system to the Data Center Manager.  Changes in the power distribution configuration at the rack in the data center can now be made without shutting off power panels, powering down branch circuits, or disabling busways.  The zPDS system enables the Data Center Manager to reduce risk, while maintaining up-time!

More and More Organizations are Forbidding Energized Changes for Safety Reasons.

  1. Arc-flash is a real concern.
  2. NFPA 70E states “Local circuit disconnects are useful to insure that units are not installed or removed while under load. This is a particular concern to avoid arcing.”
  3. OSHA mandates that work on electrical systems in data centers be done while de-energized whenever possible.
  4. Electricians are refusing to make changes to energized power distribution devices

Easy Power Configuration Changes

zPDS simplifies the management of power reconfigurations by making the cabinet the locus of power reconfigurations. The zPDS outputs are four NEMA L21/22-30R twist-lock receptacles or six NEMA L21/22-20R twist-lock receptacles. The zPDS product line includes plug-adapters to convert the three phase output to whatever three-phase, split-phase or single phase plug type that is needed. It also includes adaptor cables to connect equipment such as wiring harnesses for blade servers and other specialty equipment. As power reconfigurations are necessary, changes can be made by using a common or custom zPDS adaptor cable eliminating the risk, the time and the expense of having an electrician pull another power whip and consuming additional PDU breaker positions or install another busway tap box.

A Sampling of Zonit 20A/30A Plug Adapters

Superior Protection Against Power Overloads

The zPDS reduces the domain of failure when branch circuits are overloaded. It has Circuit Breaker protection on each phase of each output. Depending on the configuration chosen, the zPDS has either 12 or 18 fast acting circuit breakers to protect each phase of each output. This gives the advantage of manually turning off selected devices within a rack for maintenance while leaving the remainder of the equipment powered on. Additionally, if an over amperage condition occurs, only a portion of the equipment is powered off rather than the whole rack. zPDS breakers are thermo-magnetic with Curve 62 and they open before a branch breaker opens. They function accurately and repeatedly. By comparison; most plug strip breakers are thermo-only and will not reliably open before branch circuit breakers, which means the entire plugstrip will be powered down by an overload.

Statistical Phase Balancing

The zPDS family is the only power distribution solution in the industry that has patented power phase load balancing and addresses the problem of neutral harmonic currents (NEMA reference: NFPA 70 NEC, Article 400-5). It ensures optimum load balance, lowers site electrical costs, delivers full utilization of site PDU’s/plugstrips, and faster device installation and equipment upgrades. 

 zPDS Deployment Methodology

The zPDS can easily be deployed into existing data centers or new builds, incrementally build-as-you-go or done all-at-once. The key is to plan the maximum redundant power capacity you want to deploy for each cabinet and then deploy the power whips or busway tap boxes needed to do that. The zPDS system is then deployed to power one or more cabinets as and when needed and all future changes are made at to it. This methodology will power almost all ITE equipment, it is rare to find any equipment that requires more KVA than a 30A three-phase output can deliver.

A summary of the deployment and operation of the system, step-by-step:

  1. Install A-B 3ϕ 30A, 40A or 60A power whips or busway taps @ 208V, 415V or 480V to deliver your chosen maximum planned redundant power density.
  2. Provision 20A, 30A, 40A or 60A per cabinet in single-phase, split-phase or three-phase output, which can be A-B redundant or non-redundant, as you choose.
  3. Deploy zPDS units as and when required to support from 1 to 6 powered cabinets using Zonit plug adaptors at the cabinet to configure any type of single-phase, split-phase or three-phase receptacles to power plugstrips or direct connections for either 20A or 30A  IT equipment loads.
  4. As power demands shift, either plug new zPDS units into available power whips or re-configure cabinet power using existing zPDS units and Zonit plug adaptors; no need to pay for expensive power whip or busway re-configurations by electricians.

All changes occur at the zPDU system level, no changes are made to the power panels, whips or busways, so you don't power them down.

An example deployment of 30A 3ϕ input zPDS system - a silent movie

 

Summary

The Zonit Data Center Power Distribution System eliminates the need to use electricians and schedule painful downtime to reconfigure data center power at the rack. It minimizes the ongoing cost of changes to the power distribution system which industry studies show can be over $200 per rack per year. The savings for even small to medium data centers can be over 1/2 million dollars during a 20 year lifecycle.

The zPDS has been in the market over ten years and is used by organizations such as Eastman Kodak, Desert Research Institute and Colorado State University.

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