phytron
21
MA 2107-A005 EN
5.1 Calculation and Connection
For calculation and connection of the supply unit, the following instructions should be
followed:
1.
All
mating connector terminals indicated in the connecting diagram must be
connected to the cable.
Example: + U
B
must be connected to the pins 12a, 12c, 14a and 14c.
2. The cable cross section of the supply wires depends on the motor current. We
recommend: 0.1 mm
2
per 1 Ampere motor current. If possible, twist into pairs the
mains supply leads and the phase leads.
3. If the supply leads between the mains and the MSX are longer than 500 mm,
connect a capacitor (C2, approx. 68
μ
F/200 V - refer to figure 8) as close as
possible to the connector. This capacitor must be adapted for switching applications
and have a high ampacity (High Ripple Current) e.g. Rubycon series BXC,
68
μ
F /200 V. We recommend to parallel six capacitors with every 68
μ
F/200 V for
increasing the life-time of the MSX capacitor to get a total of 408
μ
F/200 V.
4. Transformer, load capacitor:
Transformer
U
I
85 V
AC
14
A
Load capacitor C1
10 000
μ
F
The power indications for the transformer and the load capacitor are "worst-case"
values, i.e.: computed for a maximum motor power, permanent BOOST function,
activation and a 100 % load factor.
The true values must be determined in function of the real operating conditions.
For the load capacitor, a value of 1,000
μ
F per Amp of motor current can be used.
The thermal limit values of the transformer must never be exceeded.
The internal resistance of the supply module must be good enough to avoid that the
DC voltage drops more than 15 % below the peak value, at maximum load. It is
obtainable with a transformer regulation of 3 %.
5. Rectifier:
The rectifier must be adapted to dissipation losses up to 2 Watts per Amp.
If necessary, mount a heat sink.