GM International PSD1206, Инструкция по эксплуатации

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PSD1206 - PSD1210 - SIL 3 - SIL 2 Switching Power Supply 24 Vdc G.M. International ISM0076-7
MODEL PSD1210
+ + - - - + L/+ N/-
=
_
CS
C
urrent
Sh
ar
in
g
Fault
Output 1
Supply
Input 1
24 Vdc
Output Bus
MODEL PSD1210
+ + - - - + L/+ N/-
=
_
CS
C
urrent
Sh
ar
in
g
Fault
Output 2
Supply
Input 2
Connection for current sharing
SIL 3
Draft about connection of 2 units PSD1210 in parallel mode.
Maximum load current
required to the power
supply system
(A)
Number of power supply units
at least required to satisfy
maximum load current
N
Number of power supply units,
with redundancy required for
normal operation of system
N+1
Number of power supply units,
with redundancy required for
normal operation and during
T-proof periodic test of system
N+2
10 1 2 3
20 2 3 4
30 3 4 5
40 4 5 6
50 5 6 7
For NE load:
a) SIL 2 with T-proof = 1 year;
b) SIL 2 with T-proof = 3 years.
For ND load:
c) SIL 1 with T-proof = 5 years;
d) SIL 1 with T-proof = 10 years.
During T-proof of each power supply
unit, the power supply system can not
sustain the maximum load current
because redundancy (N+1) is absent. For NE load:
a) SIL 3 with T-proof = 3 years or
SIL 2 with T-proof = 10 years;
b) SIL 3 with T-proof = 6 years or
SIL 2 with T-proof = 10 years.
For ND load:
c) SIL 2 with T-proof = 9 years or
SIL 1 with T-proof = 10 years;
d) SIL 2 with T-proof = 10 years.
During T-proof of each power supply
unit, the power supply system can
sustain the maximum load current but
SIL value changes from SIL 3 to
SIL 2 (for NE load) or from SIL 2 to
SIL 1 (for ND load), because
redundancy (N+2) is absent. For NE load:
a) SIL 3 with T-proof = 3 years;
b) SIL 3 with T-proof = 6 years.
For ND load:
c) SIL 2 with T-proof = 9 years;
d) SIL 2 with T-proof = 10 years.
During T-proof of each power supply
unit, the power supply system can
sustain the maximum load current
and maintain SIL 3 value (for NE
load) or SIL 2 value (for ND load),
because redundancy (N+2) is
present.
Number of power supply units connected in parallel for different maximum load currents required to the power supply system.
To maintain the power supply system safety integrity level, SIL 2 (ND loads) or SIL 3 (NE loads), also during the T-proof periodic test, in addition two redundant units for each
system are required.
If N is the number of power supply units connected in parallel, for the maximum load current required to the power supply system without redundancy, the total number of modules
must be N+2.
Maintaining SIL level during T-proof test in redundant architecture