Zalman ZM460B-APS 460 W Power Supply Review

Secondary Analysis

Zalman ZM460-APS uses six Schottky rectifiers on its secondary.

The maximum theoretical current each line can deliver is given by the formula I / (1 – D), where D is the duty cycle used and I is the maximum current supported by the rectifying diode. Just as an exercise, we can assume a typical duty cycle of 30%. Of course the maximum current (and thus power) this line can really deliver will depend on other components, especially the coil.

The +12 V output is produced by two MBR3060CT Schottky rectifiers in parallel, each one supporting up to 30 A (15 A per internal diode at 125° C). This gives us a maximum theoretical current of 43 A [(15 A x 2)/(1 – 0.30)] or 514 W for the +12 V output. SilverStone Strider ST50F uses different rectifiers, but with the exact same limits. Zalman ZM360-APS uses rectifiers with lower current limits (maximum theoretical current of 29 A and power of 343 W).

The +5 V output is produced by two MBR3045N Schottky rectifiers, supporting up to 30 A at 100° C each (15 A per internal diode). So the maximum theoretical current the +5 V output can deliver is of 43 A or 214 W. These are the exact same components used on both SilverStone Strider ST50F and Zalman ZM360-APS.

The +3.3 V output is produced by another two MBR3045N Schottky rectifiers, supporting up to 30 A at 100° C each (15 A per internal diode). So the maximum theoretical current the +3.3 V output can deliver is of 43 A or 141 W. These are the exact same components used on both SilverStone Strider ST50F and Zalman ZM360-APS.

Figure 12: +12 V rectifiers, +5 V rectifiers and +3.3 V rectifiers.

In Figure 13, you can see the thermal sensor available below the secondary heatsink, in charge of changing the fan speed according to the power supply internal temperature.

Figure 13: Thermal sensor.

This power supply uses a PS223 monitoring integrated circuit, which is in charge of the power supply protections, like OCP (over current protection). OCP was really activated, as we will talk about later. This IC also provides over voltage protection (OVP), under voltage protection (UVP) and over temperature protection (OTP), but not over power protection (OPP).

The electrolytic capacitors from the secondary are also from CapXon and labeled at 105° C, as usual.

In summary the secondary from this power supply is identical to the secondary from SilverStone Strider ST50F but has a higher current/power limits that the secondary from Zalman ZM360-APS.