Adjust Armature Air Gap.

terminals. (Series winding and voltage regulator yoke if

improper assembly, and inspect armature stop for

terminals are not on sub-base.) If lamp does not light, it

distortion or incorrect adjustment.

indicates a faulty resistor, frequency winding or faulty

contacts on either current or voltage regulator units. If

(2) Current- regulator unit. The same limits

lamp lights, open current regulator contacts. Release

and procedures as described for voltage- regulator

current regulator contacts and open voltage regulator

applies to current regulator unit.

contacts. If lamp does not go out in each case, replace

armature affected.

g. Measure Contact Point Gap on Circuit Breaker

d. Inspect contacts on all three units. In normal use,

Unit. Measure gap between both sets of contacts. Do not

contacts will become grayed. If contacts are burned, dirty

set this gap less than 0.025 inch, but it may be set larger

or rough, file with contact point dresser parallel and length

than this after adjusting contact opening amperage. Bend

wise to armature. File just enough so contacts pre- sent

stationary contact brackets to adjust gap, and align

smooth surfaces towards each other. It is not necessary

contacts so contact is made and broken on both sets of

to remove every trace of burning. After filing, dampen a

contacts.

piece of linen tape in carbon tetrachloride and draw

between contacts. Repeat with a dry tape. Use clean

h. Circuit Breaker Adjustment.

tape for each set of contacts.

(1) Mount regulator on test stand in same

e. Adjust Armature Air Gap.

position as it is mounted on vehicle, or if this is unknown,

mount with base vertical and terminal hanging down. Use

(1) Circuit breaker unit. Use pin gage of

generator of type specified for regulator and mount on

correct limits and insert between armature and core on

test stand. Connect battery of correct voltage and

contact side and next to brass pin in core. Adjust gap by

polarity.

bending armature stop. Be sure stop does not interfere

with armature movement.

(2) Connect test stand battery ground lead to

generator frame and connect other battery lead to

(2) Voltage-regulator unit. Connect battery and

regulator terminal marked "Bat". Connect generator

lamp in series with "Arm" and "Field" terminals to indicate

"Arm" terminal to regulator "Arm" terminal and connect

when contacts are opened and closed. Insert pin gage of

variable resistance in series with generator "Field" and

correct dimension between armature and core on contact

regulator "Field" terminals. Run a ground lead from

side and next to brass pin in core. Hold armature down

generator frame to regulator ground frame. Connect

with two fingers so contact spring is not touched. Adjust

voltmeter from regulator ground frame to regulator "Arm"

gap so lamp will burn brightly when high limit gage is in

terminal.

place, and will go out or dim when low limit gage is in

(3) Polarize the generator to prevent burning

place. Adjust gap by slightly loosening screw holding

regulator contacts; remove generator field lead from

armature stop and raising or lowering stop. Tighten

variable resistance, close test stand battery switch and

screws and check gap.

momentarily touch field lead to regulator "Bat" terminal,

then connect field lead to variable resistance as above.

(3) Current-regulator unit. Check and ad- just

(4) Insert all the resistance in field circuit. Start

as described above for voltage-regulator, using correct

generator and operate at 1,000 to 2,000 rpm. Decrease

gage.

field resistance slowly, and noting voltmeter reading just

before change caused by closing of the circuit breaker.

f. Check Gap Between Contact Spring and Stop.

Decrease resistance until ammeter shows a charge of one

half current value stamped on regulator name- plate,,

then increase resistance slowly.

Note amperage

(1) Voltage-regulator unit. Hold armature down

discharge just before contacts open and ammeter reading

against core stop with feeler gage measure gap between

drops to zero.

contact spring and armature stop. If gap is not between

0.010 and 0.016 inch inspect bumper block for damage or

(5) Adjust closing voltage to specified figure by

turning thumb nut on lower end of armature spring.

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