Server Tech Sentry Smart PDU, 0U (CS-21VY-L2120)

Please note, the ServerTech CS-21VY-L2120 PDU has been discontinued. For replacement options, please contact your Server Racks Online sales representative.

The Server Tech CS-21VY-L2120 is a 0U, 21 outlet, 20A, 3-Phase Wye, 208V, NEMA L21-20P, Sentry Smart Rack PDU. 

The Smart Cabinet Distribution Units (CDU) provide reliable power distribution combined with local and remote power monitoring and environmental monitoring via IP. Use the network interface to view power, temperature and humidity levels via Web browser, or receive SNMP based alarms and email alerts when conditions exceed de ned thresholds.

Server Tech Smart CS-21VY-L2120 PDU Features:

  • Input Current Monitor: Precisely measure the aggregate current draw (in amps) on each power circuit. On-site verification of the input current with the LED digital display. Remote verification via browser or serial screen.
  • Medium Power Distribution: Single 3-Phase, 20A input feed.
  • High Density: 21 outlets per enclosure
  • IP Access & Security: Web interface, SSL, SSH, Telnet, SNMP or RS-232 access
  • Environmental Monitoring: Each Smart CDU supports two temperature & humidity probes and reports conditions through the Web interface.
  • SNMP Traps: Provide automated alerts for power and environmental conditions

Additional product specifications are below.

Server Tech Sentry Smart PDU, 0U (CS-21VY-L2120) - Click to enlarge

Server Technology

Rack UnitsZero U
Dimensions45.7"H x 1.75"W x 2.25"D

Mounting Bracket Options
Include Mounting Bracket KIT-MBVPT-1B (no charge)
No Mounting Bracket Needed

Server Tech CS-21VY-L2120 Specifications:

Height 45.7 in. (1160 mm.)
Width 1.75 in. (44.4 mm.)
Depth 2.25 in. (57 mm.)
Available Input Voltages 3-Phase Wye, 208V
Available Input Cord NEMA L21-20P
Cord Set, 10 ft (3m)
Outlets (21) IEC 60320/C13
Amperage 20A
Branch Circuit Protection Compliant to UL 60950-1

10/100 BaseT Ethernet
RS-232 (Serial)


cTUVus UL 60950-1-2003
CAN/CSA 22.2 No. 60950-1:2003
FCC Class A, Part 15
EMC-EN 55022 Class A, EN 55024

Server Tech Smart PDU Additional Features:

  • Input Current Monitoring- Exclusive True RMS current monitoring is critical to preventing overloads in high-density computing environments. LED digital displays on the CDU enclosure report the input current of each phase or branch circuit for simple load balancing.

  • Temperature and Humidity- The Smart CDU supports two external 10 (3m) probes. Each of these probes measure both temperature and humidity. Receive SNMP-based alerts or email notifications when conditions exceed defined thresholds.

  • Remote Power Monitoring- Monitor input power via IP or serial interface.

  • HTTP/HTTPs Web Configuration & Control- Use the Sentry Web interface to configure each unit's network settings. SNMP traps for environmental & power thresholds and firmware updates. Also use the Web interface to monitor key values, including amperage load(s), temperature/humidity and other environmental conditions. SSL security provides a secure HTTPs connection.

  • SNMP Management & Event Notification- The Sentry family of products supports the Simple Network Management Protocol (SNMP). This allows network management systems to use SNMP requests to retrieve information such as input power, temperature and humidity. 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 can be generated for various events, including Input Current Load Thresholds (min & max), Temperature Thresholds (min & max), Humidity Thresholds (min & max), water indication, and closed contacts (cabinet doors open/close).

  • 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.

  • Secure Access - SSH or 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.

  • Integrated Temp/Humidity Probe Support- 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 provide real-time measurements in the data center cabinet.

  • 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. Click here for the latest Firmware update.

  • LDAP/LDAPS- The sentry family of products supports Lightweight Directory Access Protocol (LDAP) Version 3 including LDAPS (LDAP over TSL/SSL). This support enable 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 configure (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 account 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
  • 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.