Magnetek IMPULSE G+ Mini, Техническое руководство

Страница: 142 / 182

IMPULSE
®
•G+ Mini Technical Manual
November 2020
Page 142
6.2 Power Section Check
6.2.1 Power Off Checks
To perform a power section check, remove the VFD’s main and control wiring from the terminal strips. Obtain reading
as specified in the table on the next page, and ensure that the reading falls within the normal reading range.
Test equipment - Analog Ohmmeter set R x 1 scale or digital multimeter set to the diode check.
Device
VOM (on Rx1 Scale)
Normal Reading
(Analog Meter)
Normal Reading
(Digital Meter)
Positive Lead Negative Lead
Input Rectifier
Bridge
*1
L1 + 7–100 Ω Approximately
0.5 V
L2 +
L3 +
- L1
- L2
- L3
L1 - Infinite
Ω
OL Displayed
L2 -
L3 -
+ L1
+ L2
+ L3
Bus Capacitors + - Observe gradually increasing
resistance Observe gradually increasing
voltage to OL
Pre-charge Resistor - Across the Resistors 100
Ω
or less –
Output
Transistors
*2
*3
T1 + 7-100 Ω Approximately
0.5V
T2 +
T3 +
- T1
- T2
- T3
T1 - Infinite
Ω
OL Displayed
T2 -
T3 -
+ T1
+ T2
+ T3
Braking Diode B2 B1 10 Ω 0.5 V
B1 B2 Infinite
Ω
OL Displayed
B2 - Infinite Ω OL Displayed
- B2 Infinite
Ω
0.5 V
*1. “+” could be any one of two (+) terminals which are labeled as +1 and +2.
*2. If the bus fuse is blown you must install a jumper across the fuse terminals to get accurate resistance measurements.
*3. If the pre-charge resistor is open, you will read infinite
Ω b and any output terminal unless you install a temporary jumper across
the resistor.
WARNING
Do NOT touch any circuit components while AC main power is on or immediately after the main AC power is
disconnected. You must wait until the red “CHARGE” lamp is extinguished. It may take as long as 10 minutes
for the charge on the main DC bus capacitors to drop to a safe level. Failure to adhere to this warning could
result in serious injury.