Operating Notes & Data; Checking With Voltmeters; Load Regulation; Effect Of Load Power Factor - Sola HD CVS Hardwired Série Mode D'emploi

Danger! High voltages are present inside the unit. Do not reach inside while it is energized. To measure voltage,
!
de-energize the unit, connect the meter, and then re-energize the unit.

6.1 Checking with Voltmeters

All input and output voltage measurements should be made with a true RMS voltmeter. A certain amount of harmonics in the
output may cause other types—particularly rectifier types—to give inaccurate indications.

6.2 Load regulation

Changes in output voltage resulting from changes in resistive loads, from no load to full load (100% pF), are approximately 4%.

6.3 effect of Load Power Factor

"Median" value of output voltage will vary from the label rating if the load has a power factor different from the unit's design. Load
regulation will also be greater as the inductive load power factor is decreased. However, the resulting median values of output
voltage will be regulated against supply line changes at any reasonable load or load power factor.

6.4 operation with Switch-Mode Power Supplies

If an MCR is used as a source for a switch-mode power supply, a slight amount of ringing may be noticed on the sine wave
output of the unit at half cycle intervals for a short duration. This ringing occurs at the point when the switch-mode power supply
current demand drops to zero. The ringing need not be a cause for concern since it is of relatively low magnitude and frequency.
Both series have been tested with a variety of switch-mode power supplies and it has been determined that the ringing does not
affect the dc outputs, nor has it been found to degrade the components of any switch-mode power supply.

6.5 effect of Frequency

Changes in the frequency of the supply voltage will be directly reflected in the output voltage. A change of about 1.8% in output
voltage will occur for every 1% change in input frequency, and in the same direction as the frequency change.

6.6 response time

An important advantage of the SolaHD principle of static magnetic regulation is its exceedingly fast response time compared
with other types of ac regulators. Transient changes in supply voltage are usually corrected with 1-1/2 cycles or less; the output
voltage will not fluctuate more than a few percent.

6.7 input Characteristics

The MCR's transformer includes a resonant circuit, which is energized whether it is serving a load or not. Therefore, the input
current at no load is approximately 35% of the full-load level, even at light or no load. Input power factor will average 90–100% at
full load, but may drop to about 75% at half load and 25% at no load. In any case, it is always leading.
10 | CVS HARDWIRED SERIES USER MAnUAL
6.0 Operating Notes & Data
Figure 7