Bay Technical Associates 400-ST1 manual Redundant Cascade Stacking Feature

Redundant Cascade Stacking Feature

BayStack 400-ST1 Cascade Modules allow you to connect up to 8 units into a redundant cascade stack. If any single unit fails or if a cable is accidently disconnected, other units in the stack remain operational, without interruption.

Figure 6 shows an example of how a stack configuration reacts to a failed or powered down unit in the stack configuration:

a.As shown in Figure 6 unit 3 becomes nonoperational.

This can be the result of a failed unit, or simply because the unit was powered down.

b.Unit 2 and unit 4, directly upstream and downstream from unit 3, sense the loss of link signals from unit 3.

c.Unit 2 and unit 4 automatically loop their internal stack signals (A and B).

The Cas Up LED for unit 2 and the Cas Dwn LED for unit 4 turn on (yellow) to indicate the stack signals are looped.

d.The remaining stack units remain connected.

Although the example shown in Figure 6 shows a failed unit causing the stack to loop signals at the points of failure (A and B), the system reacts the same way if a cable is removed (either deliberately or accidently).

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