GE Industrial Solutions CAR1212DC series - Manual (Page 13)

GE
Data Sheet
CAR1212DC series DC-DC converter
Input: -36V
D C
to -75V
DC
; Output: 12V
DC
@ 1200W; 3.3V
DC
or 5 V
DC
@ 1A
October 21, 2013 ©2013 General Electric Company. All rights reserved. Page 13
the Vprog pin is used for setting initial conditions, if different that
the factory setting. Software programming then takes over once I 2 C
communications are established.
Vout_OV[OT]_fault_limit (40[4F]): Provides the capability to change
the OV[OT] shutdown limit. No sanity check exists to ensure that the
changed value is within the expected range. However, if the value
exceeds the maximum limit, the program will default to the
maximum value.
Vout_OV[OT]_warn_limit (42[51]): OV[OT]_warning is extremely
useful because it gives the system controller a heads up that the
output voltage/temperature is drifting out of regulation and the
power supply is close to shutting down. Preemptive action may be
taken before the power supply would shut down and potentially
disable the system.
OC and OT_fault_ response (47, 50): The default response for OC is
latched on fault. The response for OT is auto_restart once internal
temperatures cool down.
Restart after a latch off: Either of four restart possibilities are
available. The hardware pin Remote ON/OFF may be turned OFF
and then ON. The unit may be commanded to restart via i2c
through the Operation command by first turning OFF then turning
ON . The third way to restart is to remove and reinsert the unit. The
fourth way is to turn OFF and then turn ON ac power to the unit.
The fifth way is by changing firmware from latch off to restart.
Each of these commands must keep the power supply in the OFF
state for at least 2 seconds, with the exception of changing to
restart.
A power system that is comprised of a number of power supplies
could have difficulty restarting after a shutdown event because of
the non-synchronized behavior of the individual power supplies.
Implementing the latch-off mechanism permits a synchronized
restart that guarantees the simultaneous restart of the entire
system.
A synchronous restart can be implemented by;
1. Issuing a GLOBAL OFF and then ON command to all power
supplies,
2. Toggling Off and then ON the Remote ON/OFF signal
3. Removing and reapplying input commercial power to the entire
system.
The power supplies should be turned OFF for at least 20 – 30
seconds in order to discharge all internal bias supplies and reset the
soft start circuitry of the individual power supplies.
Auto_restart: Auto-restart is the default configuration for
recovering from over-current and over-temperature shutdowns.
An overvoltage shutdown is followed by three attempted restarts,
each restart delayed 1 second, within a 1 minute window. If within
the 1 minute window three attempted restarts failed, the unit will
latch OFF. If less than 3 shutdowns occur within the 1 minute
window then the count for latch OFF resets and the 1 minute
window starts all over again.
Status_word (79): returns two bytes of information. The upper byte
bit functionality is tabulated in the Status_word section. The lower
byte bit functionality is identical to Status_byte.
Fan_speed (3B): Fan speed can be controlled either by changing the
RPM or duty cycle via register 3B. Selection of RPM or duty cycle
control is accomplished by bit 6 of the FAN_CONFIG_1_2 (3A)
command. The default mode is xxxx The speed of the fan cannot be
reduced below what the power supply requires for its operation.
The number represented in register D6 is an unsigned number, it is
not in linear format.
Mfr_ID (99): Manufacturer in ASCII – 5 characters maximum,
General Electric – Critical Power represented as,
GE-CP
Mfr-revision (9B): Total 4 bytes
Each byte is partitioned into high and low nibbles.
Example: FF is read as 16.16
11 is read as 1.1
Series Hardware Rev Primary µC Secondary µC
Mfr_serial (9E): Product serial number includes the manufacturing
date, manufacturing location in up to 15 characters. For example:
13KZ51018193xxx, is decoded as;
13 – year of manufacture, 2013
KZ – manufacturing location, in this case Matamoros
51 – week of manufacture
018193xxx – serial #, mfr choice
note: if the additional xxx space is not utilized then F’s are filled
in, (i.e. 018193FFF), ensuring that the actual serial number is clearly
identified.
Invalid commands or data: The power supply notifies the MASTER if
a non-supported command has been sent or invalid data has been
received. Notification is implemented by setting the appropriate
STATUS and ALARM registers and setting the SMBAlert# flag. An
invalid command always returns a value of 0 x 00.
Control and Read accuracy:
The estimates below are believed to be reasonable under most
operating conditions. However, these are typical numbers and not
hard bound values that cannot be exceeded. In most nominal
operating conditions the returned values are significantly better
than these estimates.
FUNCTION ACCURACY
Vout_command ± 3%
Vout_OV_fault_limit ± 3%
Iout_OC_warn_limit ± 4% of FL
OT_warn_limit ± 5°C 8
Read_Vout ± 3%
Read_Iout ± 4% of FL
Read_temperature ± 5°C 9
EEPROM
The microcontroller has 96 bytes of EEPROM memory available for
the system host.
Another separate EEPROM IC will provide another 128 bytes of
memory with write protect feature.
LEDs
Three LEDs are located on the front faceplate. When the LEDs are
ON GREEN then input and output are normal.
When the FAULT_LED is RED, then a fault condition exists and the
power supply may not provide output power. The table below
further defines these states:
8 Accuracy is estimated near the shutdown point around 100°C. At lower
temperatures the accuracy is much reduced.
9 Accuracy is estimated near the shutdown point around 100°C. At lower
temperatures the accuracy is much reduced.