GAI-Tronics 295-001W, 295-001F Analog Clean Phone - Manual (Page 16)

P UB . 42004-484E
A NALOG C LEAN P HONE
®
T ELEPHONES P AGE 16 of 33
f:\standard ioms - current release\42004 instr. manuals\42004-484e.docx
01/15
External Power
The Plug-in Power Supply provided with each telephone requires 100–240 V ac input to provide a 5 V dc
output to the unit. The power supply’s connectorized, 4-foot power cable plugs into P18 on the Push
Button Switch PCBA. Refer to Figure 4 on page 11, and see Figure 9 on page 20 for jumper locations.
The No. 40411-005 Power Supply is provided with a 4-foot cord for connecting the Clean Phone ® .
Additional wire may be spliced to the existing power supply cord to obtain the desired distance to the
telephone.
The distance between the telephone and the 5 V dc power source is limited only by the maximum
allowable wire resistance, (32 ohms). See Table 2 for calculated distances for standard wire sizes. When
using No. 24 AWG wire, the 5 V dc power source can be located up to 270 feet, 82 meters, or 0.05 miles
away from the telephone. Paralleling pairs of the same gauge wire will increase operating distance by a
factor of 2.
Table 2. Calculated Distance for Standard Wire Sizes
AWG No. Feet Meters Miles
24 270 82 0.05
22 430 131 0.08
20 690 210 0.13
18 1095 333 0.20
16 1740 530 0.33
14 2770 844 0.52
N OTES :
1. The power supply should never be plugged into an electrical outlet until installation is complete.
2. Each Clean Phone ® requires its own, dedicated 5 V dc power source for proper operation.