Cabletron Systems STHI-44, STH-22, 42, 24 manual Ring Sequence, Power Supply Requirements

Ring Sequence

Note: When cancelling a MIB override, the user may have to perform the switch and power-cycle procedure twice (as described in the steps below) to actually change the STH hub’s ring speed by the switch.

To return to switch control from an MIB overridden Ring Speed setting:

1.Regain switch control. Change the current switch setting and power- cycle the STH. Regardless of the final desired speed, the user must toggle the switch opposite its current position and then power-cycle the STH to put a switch-position change into effect, cancelling the MIB override.

2.Select the desired ring speed. If the Ring Speed switch setting is not yet the desired setting (it may be the same as the former setting from the MIB command), the user must again change the switch setting and power-cycle the STH to complete the change from the MIB- commanded speed setting to the desired switch-set speed setting,

2.6.2Ring Sequence

When STH hubs are stacked, they are interconnected via the intelligent hub to create a larger ring network. The ring sequence for the stations on the ring (the order in which stations are logically arranged on the ring) is determined by the physical location of each TCU connection in the stack. It progresses in ascending stack number and port number order. The sequence is changed each time a station is inserted or de-inserted from a ring.

To determine the ring sequence, consider only those ports inserted into the ring. Begin with the STH numbered lowest in the stack and list (in ascending numerical order) the number of each inserted port. Repeatedly move to the next STH and list the inserted ports in numerical order until all ports inserted into the ring have been listed. The order is continuous, wrapping directly from the stack’s last inserted port to the first—from the bottom of the list, right back to the top.

2.6.3Power Supply Requirements

Note: The STH has a universal power supply which will accept input power from 90 to 264 VAC, 47-63 Hz.

The power supply has two outputs of +5 volts and +12 volts. The maximum output power is 20 watts and the minimum efficiency is 65%

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