Brother BAS-311A Service Manual

rzl Voltage measurement
1. Checkng the control voltage
ru·m on power while connecting the connector P8 to the control PCB, then measure the voltages
between pins 1 and 2, 3 and 4, and between 5 and 6 of connector P1.
Check points of P8
on the control PCB
Acceptable value
Between pins 1 and 2
Approx. 65 Vdc
Between pins 3 and 4
Approx. 11 Vdc
Between pins 5 and 6
Approx. 25 Vdc
2. Checkng the + SV source
Turn
on power while connecting the connector P7 to the control PCB, then measure the voltage between
pins 1 and 2 of connector P7.
3. Checkng solenoids' voltages
P1
1
Check points of P7
on the control PCB
Between pins 1 and 2
Acceptable value
Approx.
65 Vdc
(1) Turn off the power.
Remove P1 from J1, and measure each solenoid's
resistance.
Resistance values are different according to the
sewing machine model.
Check points Solenoid Value
304A 326A 341A
311A
326LA
342A
Between Intermittent
Resistance 50
12n
~
pins1 and2 presser foot
Voltage
12V
20V
_/"
Proslerfoot(Oftly
Resistance 50
./'
~
forsolennl
./'
~ Between
tpedfb11oct)
Voltage
10V
pins3and4
Tension
Resistance
:;?'
50 _/"
release
Voltage
~
20V
~
Between
Thread
Resistance
50 sn
100
pins5and6 trimmer
Voftege
30V
20V · 60V
Between
Thread
Resistance
60
110
60
pins7and8
wiper
Voltage
30V 20V 30V
)&( Resistance and voltage values are approximate.
(2) lnsertP1 intoJ1,andturnonthe power.
·2-
Insert
the test probe from the lead wire side, and
measure the voltage.
• As for the presser foot and intermittent presser
foot solenoids, measure the voltage while raising
and lowering them.
·As for tension release, thread trimmer, and
thread wiper solenoids, start sewing, then
measure the voltage upon finishing of sewing.
Since,
in this case, the indicator only oscillates
very briefly, the value is used as a rough
measure.
Each voltage value is as in the above table.
... _.,.,.
From the library of: Superior Sewing Machine & Supply LLC

Brother BAS-311A Specifications

General

Brand	Brother
Model	BAS-311A
Category	Sewing Machine
Language	English