beautypg.com

9 wire selection, Wire current capacity – AMETEK ReFlex User Manual

Page 247

background image

DC Power Supplies

ReFlex Power™

6-44

M380056-01 Rev K

signal will open the sense / output isolation relays, and turn off the front-panel
output indicator. The condition of the ENA signal is stored in the FAULTS
register; it could be queried using the SCPI command, STAT[n]:MOD:FAUL?.

6.4.9

W

IRE

S

ELECTION

Input/output wiring must have a current carrying capacity compatible with the
current rating of the ReFlex Power™ system. The maximum current rating of a
wire is dependent on the materials used in its construction, and is primarily
limited by the insulation. The current must be limited so that the temperature rise
of the wire does not result in an operating temperature that exceeds the rating of
the wire.

W

IRE

C

URRENT

C

APACITY

Table 6-14 shows maximum current ratings, based on a cable of three
conductors, that will produce an approximate 30ºC temperature rise above
ambient. When wiring must operate in areas with an elevated ambient
temperature or bundled with other wiring, heavier gauges or higher temperature-
rated wiring should be used.

Although wire with higher temperature rated insulation will allow operation at
higher currents, the total voltage drop would also be increased for a given wire
gauge. For applications where voltage characteristics, such as regulation, are
important, it may be necessary to size the wire based on total voltage drop
instead of temperature rise.

Table 6-14. Wire Data

AWG

COPPER AREA,

CM

2

RESISTANCE,

/M AT 20°C

RESISTANCE,
/M AT 100°C

CURRENT RATING,

A FOR 30ºC RISE

6

0.133

0.0013

0.0017

54

8

0.0837

0.0021

0.0028

40

10

0.0526

0.0033

0.0044

27

12

0.0331

0.0052

0.0069

21

14

0.0208

0.0083

0.011

16

16

0.0131

0.0132

0.0174

12

18

0.00823

0.0209

0.0276

10

20

0.00518

0.0333

0.044

7.5

22

0.00326

0.053

0.07

5.5

This manual is related to the following products: