Service manual

Service Manual
Hard disc drive
The hard disc drive used on the workstations (except
discless) is an internally-fitted SCSI device. For more
information on the types of SCSI drive usable, see the
SCSI Expansion Card User Guide.
Case colour specification
The colour of the cream plastic mouldings, the main case
and the back panels which are painted, is Pearl White
RAL 1013C.
The colour of the light grey front sub-moulding and the
light grey keyboard keycaps is Pantone warm grey 3.
The colour of the darker grey keytops is Pantone warm
grey 6.
Power supply
Performance characteristics
Performance
Min
Nom
Max
Units
Input voltage (47-53 Hz)
198
220/
240
264
Vac
*Input voltage (57-63 Hz)
98
110
132
Vac
Output voltage VO1
4.9
5
5.1
Vdc
Output current 101
1.5
-
12.2
Amps dc
Output ripple and noise VO1
50
mV pk-pk
BW 0-20MHz
Overshoot VO1
0.1
Vdc
Overvoltage prot VO1 (thrshld)
5.8
7.0
Vdc
Surge output current 101
-
14.5
Amps dc
Surge output current duration
-
-
1.0
Sec
Output voltage VO2
11.4
12
12.6
Vdc
Output current 102
0
-
3.2
Amps dc
Output ripple and noise V02
100
mV pk-pk
BW 0-20 MHz
Overshoot VO2
0.2
Vdc
Surge output current 102
-
4
Amps dc
Surge output current duration
-
-
10.0
Sec
Output voltage VO3
-4.5
-5
-5.5
Vdc
Output current 103
0
-
0.3
Amps dc
Output ripple and noise V03
50
mV pk-pk
BW 0-20MHz
Overshoot VO3
0.1
Vdc
Efficiency
63
-
%@max Id,
nominal I/P volt
Total output power
-
-
100
Watts cont.
122
Watts srge
'Manufacturing option
DANGER
THE POWER SUPPLY IS A SEPARATE
REPLACEABLE MODULE, AND CONTAINS NO USER
SERVICEABLE PARTS.
ALL ACORN POWER SUPPLIES CONTAIN
HAZARDOUS VOLTAGES AND MUST NOT BE
MODIFIED OR REPAIRED.
POWER SUPPLY UNITS MAY ONLY BE FITTED BY
AN AUTHORISED ACORN SERVICE CENTRE.
SAFETY EARTH CONTINUITY TESTING MUST BE
CARRIED OUT WHEN ANY POWER SUPPLY IS
FITTED.
Part 1 - System description Issue 2, June 1991 1-15