How is a current carrying wire placed in a magnetic field so that magnetic field does not act on it?

When the current carrying wire is placed parallel or anti-parallel to the magnetic field then and only then the magnetic field does not act on it.

The magnetic force depends on four things:

•Amount of current

•The strength of Magnetic field

•Length of the wire which remain in the magnetic field

•And the angle between the current carrying conductor and magnetic field.

The most important criteria here is the angle between the current carrying conductor and the magnetic field. If the angle is 0° or 180° then there will be no force acting on the wire. But if the angle is 90° the force will be maximum. If you observe the pattern it goes on like that, at 0° the force is 0 but as the angle increases the force increases and at 90° the force reaches its maximum value. And then again it starts decreasing and it becomes 0 at 180°.