Data Center Power Glossary

20-Amp Power Input Support: 20-amp Power Input Support. IEC320/C20 power inlet receptacles support any power cord with IEC320/C19 power connector (PTCORD-XX).

24-Character Outlet Receptacles Names: Use the firmware interface (Web or serial) to edit individual outlet receptacles. Identify each receptacle with the device's serial number, IP address, asset allocation #, department or any other method to individually name outlets.

3 Phase Power: 3 phase power distribution for high-density, high-power demand equipment cabinets. Input current monitoring of each phase allows for proper load balancing of each rack mount power distribution unit. Switched units provide remote power management while Smart units provide remote power monitoring and Metered units provide local input current monitoring.

The -3Ph extension on a product indicates a 3 Phase power product.

3-Phase Delta / 3~Delta: 3 ~ Delta products differ from 3~Wye products in that they have only 4 conductors inside of the cord, there is no "neutral" conductor in a Delta configuration. Thus, 3~Delta products are only capable of delivering 250V power output.

3-Phase Wye/ 3 ~Wye: 3 ~Wye product is a 5 cord configuration with three "hot" wires, one "neutral" wire, and one "ground" wire. The neutral conductor found in 3~Wye cords allows the output of 110V and/or 220V; this option allows cabinet power distribution unit configuration for either voltage which is popular in Data Center environments due to equipment demands.

30 Amp Power Input Support: 30-amp power input support provides hard-wired 10' cord and appropriate L5-30 or L6-30 plug type.

AC- Alternating Current: AC (alternating current) refers to when the flow of electric charge periodically reverses direction. An electric charge would for instance move forward, then backward, then forward, then backward, over and over again.

Add a Second Tower: Connect an Expansion Cabinet PDU to any Switched Cabinet PDU to control two power input circuits and manage outlets (individual or groups) under 1 IP address - our exclusive strategy for managing dual power-supply servers.

Amps: Amperes or Amps are a standard measurement of electrical current for how much electricity is moving through a wire at a set time. The amp draw is calculated by the electrical requirements of the devices plugged in, and is regulated by a circuit breaker or fuse.

Apparent Power: Apparent Power is the product of root-mean-square (rms) voltage multiplied by rms current and the measurement by which power companies bill.

Authentication: 16-character Username & Password required for network administrators & user accounts. Multiple user accounts can be established with access rights only to designated outlets.

Branch Circuit Protection: Sentry PDUs are safety-agency certified to the new UL 60950-1 standard (CSA/UL/TUV) & the National Electrical Code (NEC), which require branch circuit protection for receptacles.

Circuit Breaker Protected Outlets: Power outlet protection provided by a thermal circuit breaker.

Crest Factor: Crest factor is the ratio between the instantaneous peak current required by the load and the RMS current. High crest factor can lead to overheating of power supply components.

Data Center Infrastructure Efficiency (DCiE): DCiE is the reciprocal calculation of PUE. 1/PUE = (IT Equipment Power x 100%)/Total Facility Power

DC- Direct Current: In direct current (DC), the flow of electric charge is only in one direction. This is in contrast to AC or alternating current.

Firmware Flash Upgradeable: Access new firmware updates via FTP for new firmware features and code releases. An update to the firmware does not affect the status of the power outlets.

Fuse Protected Outlets: Power Outlet protection provided by fuses.

High-Amp In-Rush Protection: High-Amp In-rush relays accommodate the extremely high power in-rush spikes from today's switching power supplies.

Horizontal 2U Rack Mount: 19" rack mount enclosure.

HTTP/HTTPS Web Configuration & Control: Use the Sentry Web interface to configure each unit, including network settings, outlet naming & grouping, SNMP traps for environmental & power thresholds, and firmware updates. Also use the Web interface to control individual or group outlets and monitor key values, including amperage load(s), temperature/humidity, and other environmental conditions. SSL security provides a secure HTTPS connection.

IEC: International Electrotechnical Commission has a set of standard receptacles and outlets. Popularized because IEC plugs can output either 125 volts or 250 volts according to the cord that is plugged into them. Configurations most commonly used in Data Center Operations include C13 to C14 and C19 to C20.

Integrate Environmental Monitoring: The EMCU-1-1 integrates easily with the Power Tower XL, or other Sentry Remote Power Manager. Locate the EMCU in an equipment cabinet with a unit, link it to the unit, and view temperature, humidity, water sensing, and dry contact closures from the same web interface you use to manage & monitor the power.

Integrated Temp/Humidity Probes: Two (2) RJ-style connectors located on the face panel of the PDU's enclosure provide support for two (2) Integrated Temperature & Humidity Probes with ten-foot (10') cables to provide real-time measurements in the data center cabinet.

LDAP/LDAPS: The sentry family of products supports Lightweight Directory Access Protocol (LDAP) Version 3 including LDAPS (LDAP over TSL/SSL). This support enables authentication with LDAP servers; user accounts do not need to be individually created locally on each Sentry device.

This allows administrators to pre-define and configures (in each Sentry product, and in the LDAP server) a set of necessary LDAP groups, and access rights for each. User's access rights can then be assigned or revoked simply by making the user a member of one or more pre-defined Sentry LDAP groups. User accounts can be added, deleted, or changed in the LDAP server without any changes on individual Sentry products.
Sentry LDAP support has been tested in the following environments:
- Microsoft Active Directory (MSAD)
- Novell eDirectory (eDir)
- Open LDAP

LED Digital Display Input Current Monitor: Easy viewing display on the face of the enclosure that reports the True RMS Power Monitoring of the aggregate load on the power circuit (in amps).
The Input Current Display allows installation engineers to verify the real-time current draw on the power circuit.
This eliminates the guesswork of estimating the current draw and prevents the costly mistake of 1) overestimating and requiring extra power drops installed or 2) underestimating and overloading a circuit - putting the enter cabinet at risk if a circuit breaker at the main cabinet PDU trips.

Load Sense -Input Current Monitor Per Outlet: Individual input current monitoring ("Load Sense") provides real-time power measurement of the load in amps on each power inlet, accessible via firmware interface.

Multiple Concurrent Users: Multiple concurrent users allows several users to be logged into a Sentry at the same time. In this way, different users, with access rights to only their equipment, can reboot their device(s) when they need to, without waiting for another user to log out of the Sentry unit.

NEBS Compliant: Meets NEBS Level One and Level Three requirements for colocation in a BellCore (Telcordia) central office.

NEMA: National Electrical Manufacturers Association set of standard plugs and receptacles. NEMA nomenclature addresses the part configuration by locking ability (if applicable), 5 for 125V, 6 for 250 Volt, dash (-), followed by the amperage rating (20A, 30A) and a P for plug or R for the receptacle. I.E. 5-20R is a 125V twist lock receptacle for 20Amps.

Optional Secure Global Modem: An optional field-replaceable global secure modem that supports 56Kbps operation, Call-Back Security, and remote configuration. It is approved for use in 48 countries. Additionally, the internal modem option and Pass-Thru Port Access can eliminate multiple modems and dial-up lines and the need for an expensive terminal server. (Available in Sentry "horizontal" rack-mount models.)

POPS - Per Outlet Power Sensing: Per Outlet Power Sensing PDUs provide information per individual outlet includes: current load (A), voltage (V), power (kW), apparent power (VA), crest factor, and power factor. Using our grouping technology, power information is available per device, groups of devices (application), individual Cabinet PDU or cabinet.

Power (kW): Time rate of doing work, usually expressed in horsepower or watts.

Power Factor: Power Factor is the ratio of Real Power to Apparent Power. A Power Factor of 100% indicates perfect power, while lower values indicate that the circuit is wasting energy.

Power-Up Sequencing: Prevent a power in-rush from overloading the power circuit. In the event of a power loss, this key feature prevents all power-outlet receptacles from powering on at once - averting the potential for a power in-rush to blow a fuse or circuit breaker in the data center. Instead, the power-outlet receptacles power-on in two-second intervals, allowing each device to safely boot-up. Power-up sequencing is a default hardware setting. User adjustable.

PUE - Power Usage Effectiveness: PUE = Total Facility Power /IT Equipment Power

Rack-Mount Enclosure: 1U and 2U "horizontal" rack-mount enclosures are 17" wide and include standard mounting brackets for 19" cabinet rails 23" brackets also available.

Rack-Mount or Zero U Enclosure: Available models in either "horizontal" 17" Rack-Mount (with mounting brackets for 19" cabinet rails) or "vertical" Zero U Enclosure (includes mounting brackets).

Real Power: Real Power is the RMS value of Watts.
Real Power divided by Apparent Power is a measurement of the efficiency of power usage on a circuit.

Redundant Power: Providing two independent power sources for critical equipment to ensure Uptime. From a cabinet PDU this can be accomplished by a dual circuit cabinet power distribution unit with each cord plugged into a separate power source, or by powering 2 PDU's with different power sources (separate UPS, a UPS, and a generator, etc.)

Remote Outlet Grouping & Control: Assign outlets to a group for control of dual-power supply servers and other gear with a single command. Create an unlimited number of groups with any combination of outlets associated to each group.

Remote Power Control: Individual or group outlet remote power control to cycle power and reboot any selected servers or other network devices. Use TCP/IP (HTTP, HTTPS, SSH, Telnet, SNMP) or RS-232 to communicate with each Sentry and rectify locked-up network devices.

Remote Reboot: A power distribution unit with remote reboot allows Data Center administrators to power cycle servers and other data center equipment remotely from any worldwide location. The ability to remotely reboot equipment allows administrators to reduce downtime and provide more efficient power management within the Data Center via direct network access to power distribution units.

Power management solutions with remote reboot can be utilized at lights out Data Center operations.

RoHS: RoHS is the acronym for Restriction of Hazardous Substances. RoHS, also known as Directive 2002/95/EC, originated in the European Union and restricts the use of specific hazardous materials found in electrical and electronic products. All applicable products in the EU market after July 1, 2006 must pass RoHS compliance.

RS-232 Control: Serial control via any device with a bi-directional serial port, including a PC, laptop, KVM switch, Console Port Access switch, or terminal server. Local or remote configuration & control.

Secure Access - SSH and SSL Protection: Secure Shell (SSH), known as Secure Socket Shell, is a Unix-based command interface and protocol for securely getting access to a remote device. Sentry supports SSHv2. Secure Sockets Layer (SSL) is a commonly-used protocol for managing the security of a message transmission on the Internet. SSL is an integral part of most Web browsers (clients) and Web servers. Sentry supports SSLv3/TLSv1.

Single Phase Power - 1 Phase Power: Distribution of alternating current electric power using a system in which all the voltages of the supply vary in unison. Single-phase distribution is used when loads are mostly lighting and heating, with few large electric motors. A single-phase supply connected to an alternating current electric motor does not produce a revolving magnetic field; single-phase motors need additional circuits for starting, and such motors are uncommon above 10 or 20 kW in rating.

SNMP Management: The Sentry family of products supports the Simple Network Management Protocol (SNMP). This allows network management systems to use SNMP requests to retrieve information and control power for the individual outlets. The Sentry includes an SNMP v1 agent supporting standard MIB I and MIB II objects. A private enterprise MIB extension (Sentry3 MIB) is also supported to provide remote power control.

SNMP traps for event notification: SNMP traps can be generated for various events, including Input Current Load Thresholds (min & max), Temperature Thresholds (min & max), Humidity Thresholds (min & max), water indication, closed contacts (cabinet doors open/close), as well as notification of any time an outlet status is changed (on/off).

Telnet Management: Telnet is a user command and an underlying TCP/IP protocol for accessing remote computers.

True RMS Input Current Monitoring: Input Current Monitoring in Sentry power products is reported as the cumulative load (in amps) on each power circuit so that data center managers can obtain the data they need to plan their power requirements and to monitor power to their IT equipment. Input Current is reported in Amps and can be viewed locally on the enclosure via an LED Digital Display and remotely, when applicable, via the firmware interface.

Underwriter's Laboratory: Official listing agency certifying the use of electrical components for use in different environments. UL listing of 60950 is often requested in Data Centers at the request of electrical inspectors.

Voltage: Voltage is also referred to as Electrical tension and measure in its SI unit, the volt. Voltage is the difference of electrical potential between two points of an electrical or electronic circuit.

Volts: A fixed value for a circuit that is a measurement of electrical potential.

Watts: Measurement of electrical power being utilized by a system. The simplest calculated of a Watt is one Amp multiplied by electrical potential of one Volt.

Trus RMS calculations taken into consideration the phases of the voltage, and shape of the current waves to a circuit in order to provide the power reading. Difference between the RMS watt value and the calculation of Volts multiplied by Amps indicates an inefficiency in how power is delivered or consumed by the circuit.

Zero U Enclosure: A vertical enclosure that occupies Zero Vertical U of rack space in the equipment cabinet. It mounts on the back rails or in the cavity space of the cabinet.