HBK CB1010, Operating Manual

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CANHEAD
CANHEAD ENHANCEMENTS
There is a new menu item under “ML74"- “ Set minimum number of CANHEADs ". This in­
formation allows different CANHEAD lines to be treated equally; measurement is then
synchronous, even if the number of assigned modules differs.
Minimum CANHEADs count
The maximum number of CANHEAD modules is 12 per line, even if the number of
subchannel blocks is lower.
All CANHEAD lines should be assigned the same minimum number of CANHEADs. This
setting is also permanently stored in ML74B.
Every change to the subchannel block count, the minimum number or the baud rate,
changes the “Maximum data rate".
If the high baud rate causes problems with bus lengths greater than 100 m, the check­
mark at “
500 kBaud " can be removed and a “ Reset " performed under “ CAN bus ".
Current in the CANHEAD line is briefly interrupted and the system is powered up.
If several ML74Bs are operated in an MGCplus housing, this can cause startup problems,
because at the moment of starting, the current at +16 V is too high (can be seen at the
POWER LED of the AP74).
The current limiter under “CAN bus" must then be used.
100% is a 2 A continuous current, 75 % is certainly sufficient for 12 modules.
10.2 Enhanced filters
New CANHEAD filters were made available in ML74B with firmware version P5.18. In
cut‐off frequencies and sampling rates, these are always 2/3 of the previous filters.