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STM 4201

The STM-4201 Staged Turbine Module has been designed both to accommodate the special requirements of multi-turbine applications and to operate with VMI’s ISM-4080/4081 family of Integrated Shutdown Modules.

When using multiple turbines to deliver a single fuel product while performing line integrity testing at the beginning of delivery, it is necessary to start the turbines in a sequenced or staged order. In multi-turbine applications, if all turbines are started at the same time it becomes impossible for a mechanical leak detector to properly monitor the building pressure in the line and to perform the leak detection function.


Features: 
The STM-4201 has many application-specific features:

  • Interfacing to VMI’s ISM-4080/4081 modules

  • Automatic sequencing of up to four turbines

  • Selection of 2, 3 or 4 turbine sequences

  • Independent control of two 2-turbine sequences

  • Automatic rotation of the lead turbine

  • Detection of alarm signals from the ISMs

  • Automatic shutdown on first alarm detection

  • Automatic skipping of disabled turbines

  • General remote alarm signal output

  • Universal input and output voltage ratings

  • Selectable 115/230 Vac module power
Specifications: 

The microcomputer based Staged Turbine Module controls the sequencing of multiple turbines used to deliver a single fuel product. The following statements outline the basic operation of the STM-4201 in a four-turbine sequence.

  • Following the application of power to the system, all turbines will be in the off condition and Turbine 1 will be designated as the lead turbine in the sequence.

  • With the detection of a dispensing request signal at the STM's Authorize A input, the first ISM module will be signaled to start Turbine 1. Leak Detector 1 will monitor the pressure in the distribution line and validate that the line is tight. The ISM will return a "Ready" signal to the STM.

  • When the "Ready 1" signal is received by the STM it will signal the second ISM in the sequence to turn on Turbine 2. Because operating pressure has already been established in the line, Leak Detector 2 will validate that the line is tight and the second ISM will return a "Ready" signal to the STM. This process is repeated until all turbines in the sequence are running.

  • When the dispensing request signal at the STM's Authorize A input is removed, all ISMs will be signaled to turn off their associated turbine. This will end fuel delivery.

  • Following the termination of fuel delivery, the lead turbine designator will be advanced to point to the second available turbine in the sequence. So, in this example, Turbine 2 will become the lead turbine when the next authorization signal is received.

  • If an ISM returns an Error signal, instead of a Ready signal, fuel delivery will be terminated. Fuel delivery may be reestablished by cycling the delivery request signal at the Authorize A input. When this is done the lead turbine designator will be incremented.

  • If the operator does not clear the Error signal from an ISM, that channel and its turbine will be removed from the sequence. This means that fuel delivery may be reestablished, but with fewer turbines in the sequence. If the Error signal is actually caused by a line leak, restarting the dispensing of fuel will result in the detection of the leak by the next lead turbine. This routine may be repeated until all turbines are off line.
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.