Agilent Technologies 6625A, 6626A, 6628A, 6629A manual Feet, Cross Section, Meters, Multiple Loads

Note	To prevent tripping of the overvoltage circuit, pick a wire size sufficient to handle the FULL output
	current of the unit no matter what the intended load current or current limit setting.

Table 4-1 lists the resistivity for various wire sizes and the maximum lengths to limit the voltage drop to 1.0 volts for various currents.

Table 4-1. Stranded Copper Wire Ampacity and Maximum Wire Lengths to Limit Load Lead Voltage Drop

	Ampacity Per Wire (Amps)			Max Length to Limit Voltage
Wire Size	2 Wire Bundled	4 Wire Bundled	Resistivity	Drop to 1 V Per Lead
				5 A	10 A	20 A
(AWG)			(Ω/ft)		(feet)
20	7.8	6.9	0.0102	20	10	5
18	14.5	12.8	0.0064	30	15	7.5
16	18.2	16.1	0.0040	50	25	12.5
14	29.3	25.9	0.0025	--	40	20
12	37.6	33.2	0.0016	--	--	30
(Cross Section
Area in mm2)			(Ω/m)
					(meters)
0.5	7.8	6.9	0.0401	5	2.4	1.2
0.75	9.4	8.3	0.0267	7.4	3.8	1.8
1	12.7	11.2	0.0200	10	5	2.6
1.5	15.0	13.3	0.0137	14.6	7.2	3.6
2.5	23.5	20.8	0.0082	--	12.2	6
Notes:

1.Ampacities for AWG wires are derived from MIL-W-5088B. Maximum ambient temp: 55°C. Maximum wire temp: 105°C.

2.Ampacities for metric wires are derived from IE Publication 335-1.

3.Ampacity of aluminum wire is approximately 84% of that listed for copper wire.

4.Because of wire inductance considerations, it is recommended that you keep your load leads twisted, tie wrapped, or bundled together and less than 50 feet (14.7 meters) in length per lead.

5.See Page 49 for information on wire gauge considerations with capacitive loads.

Note	The OVP circuit senses at the main output terminals and not on the sense leads. Thus, the voltage sensed
	by the OVP circuit could be as much as 10 V higher than the voltage being regulated at the load. Program
	the OVP trip voltage accordingly when using remote sensing. In addition, if the total voltage drop in both
	leads exceeds 10 V, a protective circuit will fire the OVP circuit regardless of the OVP setting.

Load lead resistance is an important factor relating to the CV stability of the supply with remote sensing of capacitive loads. If high capacitance loads are expected, you should not use wire gauges heavier than 12 to 14 AWG for long runs of load lead. See Figure 1-4 for more information about stability with output capacitors.

Multiple Loads

If you will be sensing the load locally (as shipped from the factory) and are connecting multiple loads to one output, connect each load to the output terminals using separate connecting wires (see Figure 4-4). This minimizes mutual coupling effects and takes full advantage of the power supply's low output impedance. Each pair of wires should be as short as possible and twisted or bundled to reduce lead inductance and noise pickup.

If load considerations require the use of distribution terminals that are located remotely from the supply, connect the power supply output terminals to the remote distribution terminals by a pair of twisted or bundled wires. Connect each load to the distribution terminals separately. Remote voltage sensing is recommended under these circumstances. Sense either at the remote distribution terminals or, if one load is more sensitive than the others, directly at the critical load.

50Output Connections and Operating Information