Is it legal to use a special subsistence minimum for judges?

I see that for calculating judges' salaries, not the general subsistence minimum is used, but a specially understated value, although the law explicitly states the application of the general amount. Does this not violate the Constitution and the rights of judges? How does the law generally explain why a separate, lower subsistence minimum is established for judges, and can judges demand a recalculation of their salaries based on the general subsistence minimum?