Toshiba VT130G1 User Manual
Page 23
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Section 5
Table 3-2 shows a test sheet that gives test points and voltages at different speeds to aid
readjustment. The following describes each test point:
TABLE 3-2
OCSCmPTtON
OF TEST
TEST POINT
TO
0
Hx
90 Hx
MKx
NO LOAD
00 Kx
FULL LOAD
saHtHAi
TYPE
S^EO REFCRE^*C£
RÉF
0 V
0 V
6 V
12 V
12 V
♦voc
«.20
mA
INPUT
IRC
204 V
5.1 V
ai6v
•
1«V
10.2 V
♦voc
V
V
0 V
25 V
i
V
S V
&S7 V
«■voc
HERTZ
or
0 ms
Jti9 ms
j
OM ms
-
ù\n ms
PULSE
HERTZ
i
T
_
SPEED REFERENCE ~ is measured at the wiper of the speed pot. at the power unit.
REF to OV. 12 VDC means maximum output of the inverter.
4 to 20 mA REFERENCE is measured at terminal IRF to OV. Potentiometer 5RH adjusts
for zero speed at 4 mA.
Voltage. Frequency REF is measured at test point REF to common. Factory set at the
voltages shown in Table 4, potentiometer 9RH can be used to adjust desired maximum
output frequency. The V/Hz ratio stays the same for proper motor operation. Potentiometer
10RH adjusts the minimum speed.
V is used to determine the V/Hz ratio. Measured at V test point to common, SV means
maximum output voltage has been reached.
HERTZ - is measured at OF test point. Hertz is a strobe pulse with a frequency 1152
times inverter output frequency. 69, 120Hz means the inverter is running 60 Hz. (This
testpoint is an open collector and requires a pullup 20K ohms resistor for readouts.)
VOLTAGE BOOST - is a V/Hz adjustment at 3 RH. Output voltage at low frequencies is
raised for more starting torque.
A procedure is described below for recalibrating the power unit assuming all poten
tiometers are misadjusted. When using an oscilloscope or frequency counter, the motor
does not have to be connected.
1.
Initial Conditions 3RH - full counter clockwise (C.C.W.), 9RH - full C.W., 10RH - full
C.C.W.
2.
Set Maximum Frequency. Run inverter. Adjust poL 2RH for
desired maximum speed
with manual speed pot. fully clockwise. Digital frequency meter will show true output
hertz.
3.
Calibrate Remote Meter. Use 1RH pot. to set scale on optional remote meter.
4.
Adjust Volts Per Hertz. Turn manual speed pot. to 60 Hz. Adjust 4RH pot. for
5 VDC @ test point “V" to Com.
5.
4 to 20 mA Input. Enable auto mode. Minimum speed at 4 mA can be adjusted with
pot. 5RH. Maximum speed at 20 mA can be adjusted with pot. 6RH. Pots. 5RH and
6RH interact.
21