Data General AViiON Series, Customer Documentation

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Preparing to Install VME Options
1-5
014–001867
NOTE: Make certain to include all devices that draw current power from the
computer unit’s power supply, but not those that draw power from
another source. For example, your calculations must include graphics
keyboards and mouse devices, but monitors, most keyboards, and
Peripheral Housing Units do not draw current from the system power
supply.
If your configuration includes devices not listed in your system
documentation, refer to the device-specific technical manuals to
determine current draw (the amount of electric current the device
draws from your power supply).
If your system reads from and writes to only one memory module at a
time, enter one memory module at “active” current draw and all others
at the “idle” or “inactive” values listed in your computer system
manual. If you have a multiple processor system that can have more
than one memory module active at a time, use active values
accordingly. See lines 3 and 4 in Figure 1–2 for an example.
3. Enter the current values for applicable VME option boards on your calculation
form. Table 1–1 lists these values.
Table 1–1 Current Requirements for VME Option Boards
Board Name
Current (amperes)
Board Name
+5 V dc +12 V dc –12 V dc
VAC/16 4.5 .25 .25
VDA/128 3.4 NA* .17
VDA/255 5.2 0.0 .055
VFC 8.0 1.0 NA*
VLC 2.8 .45 NA*
VLCi 6.0 .5** 0.2
VSA 5.0 NA* NA*
VSC/3 3.4 .07 .07
VSC/3i 3.5 .15 0.4
VTC 3.0 0.5 NA*
VTRC 2.0 NA* NA*
* Not applicable
** This value includes power drawn by the transceiver on the LAN. For a VLCi controller
without a transceiver, use the value .02.
4. Calculate the total amount of current needed by your system devices by adding
the values in each column. Enter the totals on your calculation form in the
“Total Amperes Used” column of the Power Supply/Amperage section.
5. Compare the maximum available from step 1 with your amperes used totals
from step 4.
If any current draw total exceeds the maximum available for that power source,
your proposed configuration will not work; recalculate your current
requirements and/or plan another system configuration.