SGDE02BP SERVO DRIVE

SGDE02VP 4.0AMP 1PHASE 50/60HZ 200/230VAC

SGDE03BS SERVO DRIVE

SGDE04AP 200-230VAC 50/60HZ 6A

SGDE04AP 200-230VAC 50/60HZ 6A

SGDE04AS SERVO DRIVE

SGDE08AP SERVO DRIVE

SGDE08APY1 SERVO DRIVE

SGDE08AS SERVO DRIVE

SGDE08VP(R) SERVO DRIVE

SGDE08VPR SERVO DRIVE

SGDE08VS 11AMP 1PHASE 50/60HZ 200/230VAC

SGDEA3AP SERVO DRIVE

SGDEA3VP SERVO DRIVE

SGDEA5AP SERVO DRIVE

SGDEA5BP SERVO DRIVE

SGDEA5BS SERVO DRIVE

SGDEA5VP SERVO DRIVE

where m0 is the so-called ‘primary magnetic constant’ or ‘permeability of free space’. Strictly, as its name implies, m0 quantiWes the magnetic properties of a vacuum, but for all engineering purposes the permeability of air is also m0. The value of the primary magnetic constant (mo) in the SI system is 4 107 H/m; rather surprisingly, there is no name for the unit of reluctance.

In passing, we should note that if we want to include the reluctance of the iron part of the magnetic circuit in our calculation, its reluctance would be given by Rfe ¼ lfe Amfe and we would have to add this to the reluctance of the air-gap to obtain the total reluctance. However, because the permeability of iron (mfe) is
so much higher than 0, the iron reluctance will be very much less than the gap reluctance, despite the path length l being considerably longer than the path length (g) in the air.

Equation 1.5 reveals the expected result that doubling the air-gap would double the reluctance (because the Xux has twice as far to go), MM while doubling the area would halve the reluctance (because the Xux has two equally appealing paths in parallel). To calculate the Xux, F, we use the magnetic Ohm’s law (equation 1.4), which gives F ¼ MMF R ¼ NI Am0 g (1:6)

We are usually interested in the Xux density in the gap, rather than the total Xux, so we use equation 1.1 to yield B ¼ F A ¼ m0 NI g

Equation 1.7 is delightfully simple, and from it we can calculate the airgap Xux density once we know the MMF of the coil (NI) and the length of the gap (g). We do not need to know the details of the coil-winding as
long as we know the product of the turns and the current, nor do we need to know the cross-sectional area of the magnetic circuit in order to obtain the Xux density (though we do if we want to know the total Xux,
see equation 1.6).

OTHER SUPERIOR PRODUCTS