Proportional Control of Cabinet Fan Speed

The Fan Controller proportionally adjusts cooling fan speed based on temperature which results in a much quieter cabinet environment and power savings. Reducing fan speed by half can reduce noise by 70% and greatly increase fan life.

With proportional control, the fans run at the speed required to maintain a selected temperature. If the cabinet gets hotter, the fans run faster. If the cabinet temperature sinks to a colder level, the fans will shut off completely. Conversely, if the cabinets heat up to where the temperature exceeds the selected value, the fans will run maximum speed.

The selected value is called the set point. See the control graph on the next page for the range of proportional control.

If the temperature is less the Controller ramps the fan speed down to a minimum of 30% of the fan’s full speed rating to avoid intermittent blade stalling called "cogging."

Self-Contained, Rack Mounted

The Controller is self-contained; no other equipment is required. The user supplies only the fans and power cords.

Power is applied to two receptacles and delivered to the fans via three plugs. The input power has automatic A-B switching. Fan loads of up to 8 amps can be controlled. IEC-style connectors are used.

Controls are mounted on the front panel, power is accessed through the back panel

Local or Web Control

The user normally adjusts the set point through an Internet connection. If the Internet connection is not available the user can manually adjust the set point. An internal web server is included in the Controller.

The user controls the temperature set point through an Internet connection. If the Internet connection is lost, the Controller automatically reverts to the last Web-set set-point.

Internal or External Temperature Sensing

A temperature sensor is mounted in the front of the cabinet. Additionally, four front-mounted receptacles permit four remote temperature sensors to be added. When these sensors are installed the Controller automatically selects the hottest sensor and controls the fan speed from that sensor.

This permits an installer to attach sensors to a variety of locations in a cabinet and see which area runs at the hottest temperature. The sensors can be mounted up to 20 feet from the Controller.

Web Access, E-Mail, SNMP Alerts

Each Controller is assigned an IP address. By browsing to this address, the user can adjust the temperature set point, set alarms and see graphs of the cabinet temperature values. No client software is required, only an Browser, such as Internet Explorer or Firefox is need to access the data and the graphs.

A full SMNP MIB is included so that the Controller can be integrated into a Network Monitoring System such as HP OpenView, Nagios, or MRTG.

Solid-State Power Control

A solid-state power control varies the power to the fans. Voltages of 120, 208, and 230 can be used - voltage sensing is automatic. Overload protection with a fast-acting 8 amp circuit breaker is included.

A-B power switching uses conventional power relays. If one power source fails, the other power source is brought on-line in less than 5 seconds. After the switch-over, the fans go to full speed for 5 seconds, then return to the previous setting.

Either permanent split capacitor or shaded pole fans can be controlled.

Indicators, Alarm Horn and Controls

While the Controller is designed for Web control and access, manual controls are included. Indicator status lamps, a manual set-point control knob, and a back-lit LCD display permit the user to see the operating conditions without an Internet connection.

An internal alarm horn can be set to alert the user to any conditions requiring immediate attention such as persistant over-temperature or failure of a remote sensor. A local push-button silences the alarm.

Optional Battery Backup

A battery back-up feature can be added. This permits the controller to remain in operation for eight hours if main power has been disconnected. This gives the Controller time to notify the user that line power has been lost. The battery only supports the control electronics, not the fans.

Optional Pressure Sensors

In installations where confirmation of fan rotation is required, up to four pressure sensors can be installed to measure positive air pressure created by the fans blowing. Plastic tubing carries the air pressure to the sensors. Failure of air pressure can be alarmed.

Hardware Specifications

Power Connectors

Ethernet Connector

Fan Control

Temperature Sensing

If remote sensors are connected, the Controller automatically selects the hottest sensor for use as the control variable.

Local Display (LCD)

Local Set Point Knob & Pushbutton

Manual Over-ride Conditions Logic

The primary control method is through the Web interface which is referred to as Remote Control and has three states:

Indicator Lamps, Horn & Push-button Control

Pressure Sensing (optional)

Physical

Software Specifications

The Controller is easily configured and managed though its internally-generated web page. No client software or external software is required.

Graphs and real-time data as well as e-mail alerts at user specified set-points/thresholds are supplied.

Additionally, all data can be exported to into CSV or Excel files for storage or analysis. ITW’s WatchDog Console is also available for multiple Controller monitoring from one PC.

General Features - Access Protocols

Most protocols can be disabled if desired (exceptions: HTTP or HTTPS must be enables or the unit cannot be controlled).

For most protocols the user can set the TCP/IP port number.

The following protocols are supported:

• HTTP and HTTPS (HTTP/SSL and HTTP/TLS)
• SNMP (trap and get; no set)
• SMTP/POP3
• FTP
• TELNET (airflow adjust, reboot, prog. CCAT)
• ICMP (ping)

Most device data is available in the following formats:

• HTML (human-readable)
• XML (machine- and human-readable)
• PDA (HTML specially formatted for hand-held devices)
• WAP (variant of HTML for mobile phones)
• CSV (Excel- and database-readable log data)
• SMNP
• Tabs (same screen format as RSE)
• Data Displays (existing tab, new values):
• Local Set Point Temperature: 65 to 100 degF (knob)
• Current Temperature (hottest temp sensor)
• Current Remote Set Point value
• Set-point Mode: Manual over ride or automatic
• Internal sensor: present temperature
• Remote sensors 1, 2, 3, 4, 5 values
• Pressure values: sensor 1, 2, 3, 4 (if installed)
• Alarm horn: On or Off
• Battery back-up: On or Off

Additional user-configurable device information

• Location (e.g. building, floor, room, cabinet)
• Contact name (for the administrator)
• Contact phone number
• Contact e-mail address

Control Tab

Select an action via drop-down box to be carried out on the selected action:

• Place all fans in Full Power mode
• Place all fans in Off mode
• Run mode:
• Automatic Local
• Automatic Remote
• Manual Mode

A separate configuration screen changes the friendly name on a per-outlet basis.

Alarm Tab

Alarm conditions:

• Over-temperature (over set-point condition)
• Unit placed in Manual control (local over-ride)
• Pressure sensor reads low
• Battery backup enabled
• Remote sensor unplugged
• Consistent over-temperature operation

Event Log

The event log is a web-viewable textual log, available via XML, with a timestamp that is available across all ITW units.

Even when time is not configured there still is a timestamp available in the log.

Log size is capped by an internal limit, and old log entries are dropped. The following events are logged, with detail as appropriate:

• Alarm condition entered or exited
• Remote sensor unplugged or plugged in
• Severe errors on 1-wire bus (more than "normal")
• Errors sending SNMP traps or email (SMTP and POP3)

Configuration Tab

The user authentication function allows for three types of accounts:

• Read-Only enables user to see current sensor values and retrieve data in various formats (listed above). User can see the values of some configuration parameters but cannot change them. Some screens are completely blocked.
• Fan Manager is given the same privileges as the Read-Only user plus full access to the Control page for control and configuration of fan controller as described above but is not allowed to change basic device configurations such as alarms and network access.
• Administrator is given unlimited access.

Any account may be left blank to indicate that no username/password is required; however, an account may not be left blank if a password exists for a lesser account.

For example, if the Administrator account is freely open, Read-Only access cannot be username/password-controlled.

Any account may share duplicate usernames/passwords with other accounts. For example, the same username/password may be used for both Fan Manager and Administrator.

In this case, the user is given the greatest amount of access; the more permissive account trumps the less permissive account. This feature allows users to maintain Read-Only and Administrator accounts without special requirements for a Fan Manager.

Agency Approvals

UL/cUL listed 60950, Information Technology Equipment