Home ›

ISM 4080 / 4081

When fuel is not being transferred, the pressure in the underground piping system of a gasoline distribution facility may fall due to thermal contraction of the fuel within the line. This condition may create problems during dispensing operations. The ISM 4080/4081 Integrated Shutdown Module ensures line pressure by periodically starting the submersible pump (turbine) to repressurize the line. In addition, the line is monitored for leaks, and alarms cause shutdown of the delivery system.


Features: 

The ISM 4080/4081 incorporates selectable features designed to eliminate slow-flow problems associated with poor pressure management in fuel distribution lines.

  • Automatic fuel line repressurization

  • 3 GPH line leak monitoring

  • Pressure failure alarm output

  • Sump sensor monitoring (optional)

  • Sump sensor alarm output

  • Full shutdown of pump activity when pressure alarm condition is detected

  • Full shutdown of pump activity when sump alarm condition is detected (4080)

  • Optional full shutdown of pump activity when sump alarm condition is detected (4081)

  • Pump contactor control in response to an authorization signal

  • Disable the repressure cycle based on time-of-day to allow tank testing

  • Disable the repressure cycle based on an AC input signal

  • Disable the repressure cycle based on a DC input signal
Specifications: 

The microcomputer controlled ISM executes an application program which controls the sequencing of two timers. The first determines the pump running time. The second determines the delay time following the detection of low line pressure. The following statements outline the basic operation of the ISM 4080/4081.

The four push-button switches located on the ISM's front panel are used to program the time-of-day, the pump duration time, the delay time, the disable interval, and to reset the unit to the beginning of the pump cycle.

A two-line by 16-character display is located on the ISM's front panel. Programming and system status information is presented on this display.

The timers operate synchronously with respect to a dispensing authorization signal. This means that the repressure sequence will be interrupted by the initiation of a fuel- dispensing request. When the authorization signal is turned off, the repressure cycle is reinitiated in the monitoring state.

Authorization signals will be ignored and pump operations will be terminated if a pressure or sump sensor alarm signal is detected. Pump control will be restored when the alarm condition is corrected and the reset push-button is cycled.

Operation of the pump may be disabled during periods of tank integrity testing. An active dispensing process will not be interrupted by the disable signal.

The monitoring of a mechanical leak detector provided by Vaporless Manufacturing is required for operation of the ISM. The monitoring of a sump liquid level sensor is optional.

With power applied, the ISM is active. The pump timer is the first to operate following the application of power. The pump will remain active until proper line pressure is achieved. Following the completion of the repressure cycle, the ISM enters the monitoring state looking for loss of line pressure.

Downloads:
Contact Information:

For sales and service, please contact Vaporless Manufacturing, Inc. at 800-367-0185.

For other information please call Barrett Engineering at 707-725-9898.