CPWR-AN26, Rev A, 08-2018
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The information in this document is subject to change without notice.
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table 6. The measurement points are ADC+ and ADC-.
There is an error in the silk screen
of some of the Control Board PCBs. The ADC+ marking on the silk screen of the PCB
should be ADC- and vice versa. Please see Figure 10 in Section 8 for accurate
designations (in red).
•
Increase the AC voltage to the required value (nominal voltage 230 VAC) and check that
the AC voltage is in between the universal range (110 VAC -230 VAC) (for relay to close,
the minimum required AC voltage is 105 VAC). Next, turn ON the MCB. The relay closing
sound should be audible after few seconds. Check the DC link voltage with the help of
a multimeter. It should be close to the peak of the AC input voltage.
•
Check the current drawn by the +7V,+15V and +15V_1 inputs. The current drawn should
be similar
to the specified values under “CURRENT 2” listed in table 5.
•
Check LED (D10) for frequency detection. The detected frequency must match with grid
frequency or AC source frequency. If it does not match (which can happen when the
input voltage is lower than 100V), switch OFF the AC input and switch it ON again.
•
Put sw2 in ON position and measure the output voltage. The output voltage should be
/- 3% of the set voltage. Check the currents drawn by the +7V, +15V and +15V_1
inputs. They should be similar
to the specified values under “CURRENT 3” in table 5.
•
Turn ON the 24V supply and a cooling fan that should be attached to the supply.
•
Switch ON the output load in a MAXIMUM step of up to 2 kW. The maximum load should
be no more than 5200 W for 260 VDC output voltage operation or 6600 W for 450 VDC
output voltage operation.
•
There is no output current control loop in this mode so you must size your load resistor
so that the output current does not exceed 20 A and the total output power does not
exceed 6600W. This means when VOUT is greater than 330 VDC, the output current
must be de-rated so that POUT does not exceed 6600 W. Failure to do this may result
in damage to the circuit.
•
Check for the overall AC/DC Stage efficiency and THD (Total Harmonic Distortion).
Please take the following steps in order when stopping the unit in AC/DC mode:
•
Decrease the output load in steps no greater than 2 kW (MAXIMUM) until no load.
•
Put switch sw2 in the OFF position.
•
Open MCB to remove the AC source. Turn OFF the AC source.
•
The DC link capacitors remain charged for at least 30 minutes after the circuit is turned
OFF, although you may decrease the time that it takes for the board to be fully
discharged by adding a discharge circuit to the DC link. Allow the unit to fully
discharge before turning OFF any of the digital logic/DSP power supplies, and do not
touch the unit until it has been fully discharged. Please check the DC link voltage with
a DMM to ensure that the board has fully discharged and is therefore safe to handle.