1328 Azalea Garden Rd.
Norfolk VA. 23502
757-855-6006
Fax: 757-855-3761

FOR IMMEDIATE RELEASE

Date: November 2005

Contact: Product Support (productsupport [at] bauercomp [dot] com)

Scope

This bulletin describes the additional control mechanisms added to version 1.2 of the SNGII controller. This enhancment will be available on SNGII series generators starting January 1 2006. >/p>

Serial Lead/Lag sequencing

A lead/lag flip flop mechanism has been added to the controller logic that uses the 9-pin serial port on the front of the PLC to communicate with a second generator system. The System Setpoints screen has also been modified to include additional buttons that allow the operator to set the system in one of three operating modes.

1) Single: In this mode the unit operates as a single, stand alone unit.
2) Servant: In this mode the unit will accept commands from a Master unit that will place it in either lead status or lag status.
3) Master: In Master mode, the lead/ lag control mechanism is activated and the unit will automatically switch between the Lead unit and the Lag unit every time it shuts down on final pressure. The master unit will send a message to any unit that is connected via the serial cable and is placed in Servant mode. The Servant unit will be instructed to become the lead or lag unit whichever is the opposite of the current status of the Master unit.

The Master unit will initiate a communication that updates the status of a servant unit when one of five events takes place.
a) On a timed basis: While the master unit is powered and the Start button has been pressed, a system timer will be enabled that will initiate Master/Servant communication every five minutes.
b) When the system is started (by pressing the START button).
c) When the Master unit shuts down on final pressure while acting as the Lead unit.
d) In the event the Master unit faults for any reason. (This will place the Servant unit in Lead mode by default.
e) In the event the system pressure comes within 100 psi of the shutdown setting while the Master unit is acting as the Lag unit. Once a communication event has been initiated, the Master unit will wait five seconds for a responce from the Servant unit. If the servant unit responds, indicating that it is either turned off or faulted, or the five second period expires without a responce, the Master unit will set itself to Lead by default.

For More information on Lead/Lag control, Click Here.

Modified User Interface Screens

Main Screen:
When an SNGII is shipped from the factory, it is set by default to Single. When conneecting two units together, one unit must be set for Master and the other set to Servant in order for Lead / Lag operation to commence.

Oxygen fault alarm

An oxygen alarm feature has been added to the system. If the system cannot bring the membrane outlet purity below 10% within the first 90 second of operation, the system will fault. Also, if at any time after the initial 90 seconds of operation, the signal from the O2 monitor generates a value of 0.00%, the alarm will trip while assuming an O2 sensor problem. This fault can be bypassed if required. To do so, contact to product support address at the beginning of this bullitin.