BEST ACCESS SYSTEMS
A Product Group of Stanley Security Solutions, Inc
Minimum gauge wire chart for lock circuits
The chart in Figure
2 helps you find the minimum wire gauge needed for a specific length wire run. It assumes that the lock circuit is made of
two conductor cable. The chart also factors in a 15% voltage loss at 24 volts.
Figure
2—Minimum gauge wire chart for lock circuits
10 AWG wire
12 AWG wire
14 AWG wire
16 AWG wire
18 AWG wire
20 AWG wire
Example
Do not use this
chart for any plots
made to this
shaded area.
1.500
1.375
1.250
1.125
1.000
.875
.750
.625
.500
.375
.250
.125
0
500'
1000'
1500'
2000'
2500'
3000'
3500'
4000'
Maximum
lock current
(in amps)
Total footage of two conductor cable for lock circuit (in feet)
To find the correct gauge wire
1 Determine the maximum lock current and find that value on the
left side of the chart.
2 Determine the total footage of cable to be used in the lock circuit
and find that value at the bottom of the chart.
3 Locate the intersection of current and footage. The line above or
to the right of the intersection shows what minimum gauge wire
you need.
Example
▲
Lock current: 0.18 amp maximum
▲
Total wire run: 1000 feet
Wire gauge needed: 20 AWG two conductor cable
Note:
For 12 volt locks, double the maximum lock current, then use
that value on the left side of the chart.
Installation hints
1 Wire gauge (or size) determines how efficiently the lock will oper-
ate. Consider wire gauge before installation. To find the recom-
mended minimum wire gauge for all wire runs, see Figure
2.
2 Use wire of 20 AWG (gauge) or larger. We do not recommend
using a smaller wire gauge than 20 AWG.
3 When wiring two or more locks to a single power supply, make
sure that the power rating of the power supply is 1
½
times
greater than the sum of the lock’s power requirement.
Example
For two locks powered by one supply:
▲
Lock 1 (9KW) is rated at 24 volts, 0.18 amps—24 volts
×
0.18
amps = 4.32 volt-amps
▲
Lock 2 (45HW) is rated at 24 volts, 0.75 amps—24 volts
×
0.75
amps = 18 volt-amps
Choose a transformer with a rating of at least: (4.32 volt-amps +
18 volt-amps)
×
1
½
=
33.48 volt-amps
T56090/Rev
D
1800760 ER-7991-19 J
an
201
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