TDK-Lambda GENESYS 10KW, Техническое руководство

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83-530-000 Rev G
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3.9.2 Noise and Impedance Effects
To minimize the noise pickup or radiation, the load wires and remote sense wires should be twisted
pairs to the shortest possible length. Shielding of sense leads may be necessary in high noise envi-
ronments. Where shielding is used, connect the shield to the chassis via a rear panel Ground screw.
Even if noise is not a concern, the load and remote sense wires should be twisted-pairs to reduce cou-
pling, which might impact the stability of power supply. The sense leads should be separated from the
power leads.
Twisting the load wires reduces the parasitic inductance of the cable, which could produce high fre-
quency voltage spikes at the load and the output of power supply, because of current variation in the
load itself.
The impedance introduced between the power supply output and the load could make the ripple and
noise at the load worse than the noise at the power supply rear panel output. Additional filtering with
bypass capacitors at the load terminals may be required to bypass the high frequency load current.
3.9.3 Inductive loads
Inductive loads can produce voltage spikes that may be harmful to the power supply. A diode should
be connected across the output. The diode voltage and current rating should be greater than the power
supply maximum output voltage and current rating. Connect the cathode to the positive output and the
anode to the negative output of the power supply.
Where positive load transients such as back EMF from a motor may occur, connect a surge suppres-
sor across the output to protect the power supply. The breakdown voltage rating of the suppressor
must be approximately 10% higher than the maximum output voltage of the power supply.
3.9.4 Connecting single loads, local sensing (default).
Fig.3-10 shows recommended load and sensing connections for a single load. The local sense lines
shown are default connections at the rear panel J2 sense connector. Local sensing is suitable for ap-
plications where load regulation is less critical.
Fig. 3-10: Single load connection, local sensing
3.9.5 Connecting single loads, remote sensing
Fig.3-11 shows recommended remote sensing connection for single loads. Remote sensing is used
when, in Constant Voltage mode, the load regulation is important at the load terminals. Use twisted or
shielded wires to minimize noise pick-up. If shielded wires are used, the shield should be connected to
the ground at one point, either at the power supply chassis or the load ground. The optimal point for
the shield ground should be determined by experimentation.