TM 11-6625-2958-14&P

exactly maximum rated output voltage.

5-90CONSTANT CURRENT PROGRAMMING CURRENT

5-91 Zero Current OutPut. To calibrate the zero current programming accuracy, proceed as directed in Paragraphs 5-92,5-93, 5-94, or 5-95, whichever applies to your particular instrument.

5-92Standard instrument with resistance or unity-gain voltage programming.

a.Connect test setup shown in Figure 5-8.

b.If unit is to be used in local program- ming mode, turn CURRENT controls fully counter- clockwise. If unit is to be used in remote pro- gramming mode, connect remote programming setup

(Figure 3-6or 3-7)and adjust remote resistance or voltage to zero. (minimum).

c. Connect decade resistance box between pads of position marked for resistor R117 in “ZERO ADJUST” section of main circuit board (points “G” and “H” in Figure 5-10;also see Figure 7-10).

d. Rotate VOLTAGE controls fully clockwise and turn on supply.

e.Adjust decade resistance box until dif-

ferential voltmeter reads exactly zero volts.

f.Replace decade resistance box with fixed, metal film, 1%, 1/4 or 1/8 watt resistor of same value.

5-93Standard instrument with non-unity gain voltage programming.

a.Perform Steps (a) and (b) in Paragraph

5-92.

b. Solder jumper between “wiper” pad and “-6.2V” pad of position marked for potentiometer R116 in “ZERO ADJUST” section of main circuit board (points “I” and “J” in Figure 5-10; also see Figure 7-10).

c.Connect decade resistance box between pads marked for resistor R115 in “ZERO ADJUST” section of main circuit board (points “ K“ and “ L“ in Figure 5-1 O; also see Figure 7-10).

d.Perform Steps (d) through (f) in Paragraph

5-92.

5-94Option 021 with resistance or unity-gain voltage programming.

a.Perform Steps (a) and (b) in Paragraph

5-92.

b. Rotate VOLTAGE controls fully clockwise and turn on supply.

c.If reading on differential voltmeter is not exactly zero volts, adjust potentiometer R119 (labeled “CURRENT ZERO” and accessible through hole in rear panel) until reading is exactly zero.

5-95Option 021 with non-unity gain voltage pro- gramming.

a.Perform Steps (a) and (b) in Paragraph

5-92.

b. Rotate VOLTAGE controls fully clockwise and turn on supply.

c.If reading on differential voltmeter is not exactly zero volts, adjust potentiometer R116 (la- beled “CURRENT PROG” and accessible through hole in rear panel) until reading is exactly zero.

5-96 CC Programming Accuracy. To calibrate the constant current programming current, proceed as directed in Paragraphs 5-97or 5-98, whichever applies to your particular instrument.

5-97Standard instrument.

a.Connect test setup shown in Figure 5-8.b, Disconnect strap between terminals A5

and A6 on rear barrier strip.

c.Connect 0.1%, 1/8 watt resistor of value shown below between terminals A4 and A6 on rear barrier strip.

Mode 1

Value

6259B

200 Ω

6260B

200 Ω

6261B

200 Ω

6268B

180 Ω

6269B

200 Ω

d. Connect decade resistance box in place of R30 (mounted on standoffs on main circuit board; see Figure 7-1O).

e.Rotate VOLTAGE controls fully clockwise and turn on supply.

f.Adjust decade resistance box until dif- ferential voltmeter indicates exactly 0.5Vdc.

9.Replace decade resistance box with fixed, composition, 5%, 1/2 watt resistor of same value.

5-98Option 021.

a.Perform Steps (a) through (c) in Paragraph

5-97.

b. Rotate VOLTAGE controls fully clockwise and turn on supply.

c.Adjust potentiometer R116 (labeled “CUR- RENT PROG” and accessible through hole in rear panel) until differential voltmeter indicates exactly 0.5Vdc.

5-99TRANSIENT RECOVERY TIME

5-100 To adjust the transient response, proceed as follows:

a.Connect test setup shown in Figure 5-5.

b.Repeat Steps (a) through (k) as outlined in Paragraph 5-32.

c.Adjust R47 until transient response is within specification as shown in Figure 5-6.

5-101RIPPLE IMBALANCE (50 and 60Hz Operation)

5-102 This procedure ensures balanced operation of the triac by ensuring that the conduction time