Section II
General Product Information
006-0006715 10/31/18
Rev J
22 of 44
MPS-MPPS-4000 Guide
www.synqor.com
MPPS Overload Characteristics
Unlike the MPS which has a semi-regulated output voltage, the MPPS output voltage is fully regulated.
The output voltage is determined by the user programmed value of Vset, and the maximum
output current is determined by the user programmed value of Imax. In the figure below,
the axis values of Vout and Iout are %Vset and %Imax respectively. This shows that the
MPPS will be able to maintain the programmed output voltage as long as the output current
is less than 95% of the programmed current. If Iout exceeds 95% of Imax, the output voltage
will be reduced according to Figure 9. This is referred to as “Voltage Foldback”.
As an example, consider a MPPS with Vset = 30V, Imax = 50A. The MPPS will hold Vout at
30V as long as Iout is less than 47.5A (95% of Imax). Between 47.5A and 50A, the MPPS will
reduce the output voltage to 0V. While at 0V the MPPS will limit the output current to Imax,
in this case 50A. The output voltage will return to 30V once the load has been reduced
below 47.5A.
0
20
40
60
80
100
120
0
10
20
30
40
50
60
70
80
90
100
110
Vo
ut
(%
V
se
t)
Iout (% Imax)
Figure 9: Voltage Fold Back During Current Limit, Short Circuit
