Owner`s manual

5–2 DEChub 900 MultiSwitch Owner’s Manual
Guidelines for Calculating Power Needs
The DEChub 900 MultiSwitch power supply module is an output load sharing type
power supply rated at 140 watts. Note that the sum of the combined 5-volt and
15-volt power outputs exceeds the 140-watt power rating. This power difference
gives the 140-watt power supply the flexibility of supplying the desired 5-volt and
15-volt power demands to variety of hub configurations.
Table 5–1 lists the power consumption of each component of the DEChub 900 Multi-
Switch. An example of calculating exact hub power needs is shown in Table 5–2.
Table 5–1: DEChub 900 MultiSwitch System Power
Component
+5 V +15 V Total Power
Power supply
– Each power supply module 26.0 A 4.0 A 140.0 watts
– Maximum usable power 78.0 A 12.0 A 420.0 watts
Chassis 3.0 A 0.0 A 15.0 watts
Half-height modules, no AUI
– general power guideline 1.5 A 0.0 A 7.5 watts
Half-height modules with AUI
– general power guideline 1.5 A 0.5 A 15.0 watts
DECserver 900TM 4.0 A 0.5 A 27.5 watts
DECrepeater 900TM 4.0 A 0.5 A 27.5 watts
DECrepeater 900GM 4.0 A 1.0 A 35.0 watts
DECrepeater 900FP 8.0 A 0.5 A 47.5 watts
DECrepeater 90TS 1.5 A 0.0 A 7.5 watts
DECrepeater 90FS 1.5 A 0.5 A 15.0 watts
DECconcentrator 900MX 7.0 A 0.5 A 42.5 watts
DECbridge 900MX 9.0 A 1.5 A 67.5 watts
DECbridge 900MP
8.0 A 1.5 A 62.5 watts
When many modules requiring high power, such as the DECbridge 900MX, are con-
figured in a hub, the total power required for these modules can consume the maxi-
mum usable power, thus leaving slots without power. However, these configurations
are not common.