TDI XBL 400, Инструкция по эксплуатации и программированию

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Effects Of Cable Length
Current Oscillation
The Dynaload regulation loop is designed to operate at a fast response time of 10
µ
S. This is not
affected by manipulating the slew rate. When operating in any of the constant DC modes, the
external cable length can affect the performance of the load. If the total inductance of the power
cables is excessive, oscillation could occur. It is always recommended to monitor the current
sample output to verify that the load is operating without current oscillation.
CAUTION:
If this situation occurs refer to the section on “Effects of cable inductance
on pulse loading” for recommended solutions in 2Operating Instructions .
Line Loss
If the Dynaload is not configured for remote voltage sensing, the voltage display and voltage
read-back will reflect what may appear to be an inaccurate reading.
The voltage display will indicate the voltage present at the input terminals. This number will
be affected by the current level.
Wire has resistance, and will lose voltage as the current is increased. A general rule of
thumb is to size your wire at 500 circular mils per amp of load current. This will allow a
maximum of 10 degrees centigrade rise in temperature of the wire. The resistance of wire is
approximately 107 ohms per 1000 feet for 100 circular mils of cross-sectional area.
You can use Ohm’s law (E = I x R) to calculate the line losses for your particular application.
For detailed information about the maximum current capacity of conductors refer to Table D.
Table D. Wire Gauge/Ampere Rating Reference Table
Size
AWG
MIL-W-5088
Copper Aluminum
Single
wire
Wire
bundled
Single
wire
Wire
bundled
NE
C 1
UL 2
60°C 80°C AIA 3
500
c mils/A
30 — — — — — 0.2 0.4 — 0.20
28 — — — — — 0.4 0.6 — 0.32
26 — — — — — 0.6 1.0 — 0.51
24 — — — — — 1.0 1.6 — 0.81
22 9 5 — — — 1.6 2.5 — 1.28
20 11 7.5 — — — 2.5 4.0 3 2.04
18 16 10 — — 6 4.0 6.0 5 3.24
16 22 13 — — 10 6.0 10.0 7 5.16
14 32 17 — — 20 10.0 16.0 15 8.22
12 41 23 — — 30 16.0 26.0 20 13.05
10 55 33 — — 35 — — 25 20.8
8 73 46 58 36 50 — — 35 33.0
6 101 60 86 51 70 — — 50 52.6
4 135 80 108 64 90 — — 70 83.4
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