DMC Sigma2N - Page 102

Simga2N Traction Advanced Manual– V1.3 Page 102 (166) ©2021 DMC GmbH Herten Germany
High voltage limit
The high voltage limit is the absolute limit of the controller and the motor. When the voltage is above this level,
the controller will immediate stop driving and braking the motor (stops with giving power to the motor) and
will report an error F22.
Parameters
The controller will have a set of parameters with which the high voltage cut back can be tuned. The controller
itself must be protected at all times, thus there is a higher limit which cannot be altered. The parameters can
only be tuned ‘up’ to protect the battery and motor of the user.
The parameters are:
• High voltage cut back start threshold
• High voltage cut back end threshold
• High voltage error threshold
The location, unit, range and step size of these adjustments can be found in reference in the “Menu 5 “Limits
Setup””.
Other limits
The controller may have other limits in effect (e.g. controller temperature limit or high voltage limit). The
module which is limiting the most, will apply the limit. The ‘DrvTqLim and ‘BrkTqLim’ will then show the limit
of the corresponding module.
Example
• Controller temperature limit 50 %
• Low voltage cut back limit
1)
70 %
• High voltage cut back limit
1)
30 %
• Applicable drive limit → 50 % → ‘CT’
• Applicable brake limit → 30 % → ‘HV’
1)
Of course, both a high voltage and a low voltage cut back should not occur simultaneously, but is done
here to illustrate the applicable limits.
A note on drive and brake
A traction controller is able to drive and brake a motor. Driving can be demanded by the user, for example,
forward drive or reverse drive. Braking can also be demanded by the user, for example, neutral brake and foot
brake. However, when the user changes the direction from, say forward to reverse, the vehicle must first come
to a stop before the actual direction can be changed. The controller will then use ‘direction braking’.