AXIOMATIC AX180800, Руководство пользователя

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UMAX180800, 20 Thermocouple, 2 RTD, 4 Inputs, 6 Relays Dual CAN Controller Version 1 Page: 10-71
inactive, a DM1 will be sent immediately to reflect this. As soon as the last active DTC goes
inactive, it will send a DM1 indicating that there are no more active DTCs.
If there is more than on active DTC at any given time, the regular DM1 message will be sent
using a multipacket Broadcast Announce Message (BAM). If the controller receives a request
for a DM1 while this is true, it will send the multipacket message to the Requester Address
using the Transport Protocol (TP).
At power up, the DM1 message will not be broadcast until after a 5 second delay.
This is done to prevent any power up or initialization conditions from being
flagged as an active error on the network.
The Diagnostic function block has a setpoint
Event Cleared Only by DM11 . By default, this is
set to false, which means that as soon as the condition that caused an error flag to be set goes
away, the DTC is automatically made Previously Active, and is no longer included in the DM1
message. However, when this setpoint is set to true, even if the flag is cleared, the DTC will
not be made inactive, so it will continue to be sent on the DM1 message. Only when a DM11
has been requested will the DTC go inactive. This feature may be useful in a system where a
critical fault needs to be clearly identified as having happened, even if the conditions that
caused it went away.
In addition to all the active DTCs, another part of the DM1 message is the first byte, which
reflects the Lamp Status. Each Diagnostic function block has the setpoint
Lamp Set by Event
in DM1 which determines which lamp will be set in this byte while the DTC is active. The
J1939 standard defines the lamps as ‘ Malfunction’ , ‘ Red Stop’ , ‘
Amber,
Warning’
or
‘Protect’
.
By default, the
‘Amber, Warning’
lamp is typically the one set by any active fault.
By default, every Diagnostic function block has associated with it a proprietary SPN. However,
this setpoint
SPN for Event used in DTC is fully configurable by the user should they wish it to
reflect a standard SPN define in J1939-71 instead. If the SPN is change, the OC of the
associate error log is automatically reset to zero.
Every Diagnostic function block also has associated with it a default FMI. The only setpoint for
the user to change the FMI is
FMI for Event used in DTC , even though some Diagnostic
function blocks can have both high and low errors. In those cases, the FMI in the setpoint
reflects that of the low-end condition, and the FMI used by the high fault will be determined per
Table 30. If the FMI is changed, the OC of the associate error log is automatically reset to
zero.
Table 30. Low Fault FMI versus High Fault FMI
FMI for Event used in DTC
– Low Fault Corresponding FMI used in DTC – High Fault
FMI=1, Data Valid But Below Normal
Operational Range
– Most Severe Level
FMI=0, Data Valid But Above Normal
Operational Range
– Most Severe Level