Review of the Enermax RevoBron 700W ED2 power supply / Overclockers.ua

We have previously reviewed the RevoBron power supply from Enermax, which was made with a good element base, but only met the “bronze” energy efficiency certificate. Its highlight was the presence of an external controller for controlling several fans, which allows you to bypass the painstaking setup in the UEFI of the motherboard for these purposes. This time we got the second revision of this series in the face of the RevoBron 700W ED2 model. Let’s see how it differs from its predecessor.

Enermax RevoBron 700W ED2 (ERB700AWT ED.2)

The power supply is packed in a black and red box, the package contains all the characteristics, kit and features of the device.

In the box, in addition to the RevoBron 700W ED2 itself, there is a set of detachable cables, a power cord, a set of Velcro ties, a bag with mounting screws, a bag with plastic plugs for connectors, a nylon bag and instructions. The CoolerGenie controller with cables to connect it was missing this time.

The power supply is semi-modular, the motherboard and processor power cables are soldered into the device board, the remaining cables are removable, their number and length are as follows:

• one to power the motherboard (60 cm);
• one with one 8-pin (4+4) CPU power connector (70 cm);
• two with two 8-pin (6+2) connectors for powering a PCI-E video card (50+15 cm);
• two with four power connectors for SATA devices (45+15+15+15 cm);
• one with four power connectors for IDE devices (45+15+15+15 cm);
• one adapter from IDE to FDD (10 cm).

All cables are made in the form of loops with black insulation, the wires are long enough for cases with a lower location of the power supply.

The case of the block is painted with black powder paint, the name of the series is painted on the side faces with white paint, the company’s logo is on the ventilation grille, and on the upper face of the block there is a sticker with all the characteristics of RevoBron 700W ED2. In terms of its capabilities, the block does not differ from the first revision.

The connectors for connecting modular cables are signed according to their functional purpose and have a different number of contacts, so it will not be possible to confuse them. There is no connector for connecting the CoolerGenie controller, but this is only at first glance – there is a hole in the case for it and it is present on the board, however, there is no sense in it without a controller. It seems that this is the only difference of the new block.

The model under consideration uses a platform that is already outdated by today’s standards, when modern circuitry is already used in more accessible blocks. The unit is 80 Plus Bronze certified and features an Active Power Factor Corrector with a wide supply voltage range. The power converter along the + 12V line is built according to a single-cycle forward circuit with PWM control, the so-called oblique bridge, Schottky diodes are installed at the output from the power transformer, and field-effect transistors are installed instead of the closing diode as a synchronous rectifier. The scheme is hybrid and has neither high efficiency nor good reliability. Voltages +5V and +3.3V form separate DC / DC converters from +12 V.

Inside the power supply has not changed at all. As promised, all capacitors are made in Japan. A full-fledged surge noise filter is installed at the input, part of which is soldered directly on the network connector, the input rectifier is made on one diode assembly with a small radiator, the parameters of which remain unknown. APFC consists of a C3D060D diode (9A 600V) and a pair of GP28S50G transistors (28A 500V). The charge current of the input storage filter is limited by the thermistor, the filter itself is made on a pair of electrolytic capacitors: one with a capacity of 390 uF and an operating voltage of 400 V manufactured by Nichicon, GG series (service life of 2000 hours at a temperature of 105 ° C) and the second with a capacity of 270 μF with a voltage of 400 V manufactured Nippon Chemi-Con, KMR series (lifetime 2000 hours at 105°C).

At the output after the power transformer, two Schottky diodes PFR30L60CT (30A 60V) connected in parallel are installed on the radiator, instead of the closing diode, a pair of field-effect transistors of a synchronous rectifier is installed, the parameters of which could not be considered. After the rectifier, a massive output choke is installed along the + 12V line, next to which there are Nippon Chemi-Con electrolytic Low ESR output filter capacitors – two with a capacity of 2200 uF with an operating voltage of 16 V of the KZE series (service life 5000 hours at a temperature of 105 ° C) and one 1000uF 16V KY series (lifetime 6000 hours at 105°C). Capacitors are installed close to the output reactor, which gets quite hot, which will negatively affect the life of these components.

Next to the output choke, there is a DC/DC buck converter board with a synchronous rectifier for +3.3 V and +5 V lines. The power switches are made on four SPN3006 transistors (80A 30V), which are controlled by the APW7159C PWM controller. The input power is filtered by a pair of 470 uF polymer capacitors and an operating voltage of 16 V, the output voltages are filtered by four 1500 uF polymer capacitors at 6.3 V.

Sitronix ST9S429-PG14 supervisor is installed on the main board, which monitors all output voltages and current along the +12V line, which is divided into two. The manufacturer declared the implementation of protections OPP, OVP, SCP, OCP, SIP, UVP.

The +5VSB standby power converter control circuit is made on the TNY177PN PWM controller. At the output of this node, two electrolytic Low ESR capacitors with a capacity of 1000 uF and a voltage of 16 V of the KY series manufactured by Nippon Chemi-Con are installed.

Cable connectors are installed on a separate printed circuit board, no additional capacitors were found on it.

Installation and soldering are of high quality, but in some places there is no washed off flux.

A 120 mm Enermax ED122512H-FD fan (120x120x25 mm, 12 V 0.35 A) with magnetically suspended Twister Bearings is responsible for cooling the components. The claimed operating time is 160 thousand hours, there is support for Dust Free Rotation technology, which is designed to reduce the amount of dust on the blades by operating the “turntable” in the opposite direction for 10 seconds. Of the minuses of the fan – 4-wire connection and rather high noise at maximum speed. The fan speed is controlled automatically depending on the temperature of the power components.

Test Methodology

The power supply test was carried out using a linear electronic load with the following parameters: current adjustment ranges for the 3.3 V line – 0-16 A, for the 5 V line – 0-22 A, for the 12 V line – 0-50 A. Measurement error current and voltage stand 5%, all contacts for connecting cables of the tested power supply with the same voltage are connected in parallel and loaded with the corresponding load channel. The current for each channel is smoothly regulated, and it is stable regardless of the output voltage of the unit. To accurately measure voltages, mains current and temperature, a Zotek ZT102 multimeter with True RMS was used. The output ripple level was measured with a DSO203 digital oscilloscope. For each power line, the required current was set, and the voltage at the load contacts was measured to take into account losses on the wires.

The heating test of the unit components was carried out at an air temperature in the room of 26 °C. The sensors of the Scythe Kaze Master Pro panel were installed on radiators, an APFC choke, an output choke, a DC / DC converter board, a thermocouple from a multimeter was installed under the insulation of the power transformer winding. The unit was loaded with 700 W and worked until the temperature of the power transformer stabilized, the Scythe panel readings were recorded and after the unit was disconnected from the mains, the cover was removed and the temperature of the remaining components was quickly measured.

Test results

The first test for the load capacity of the main line +12V, the current through the +3.3V and +5V lines was constant with a total load of about 100 W, the results are listed in the table.

According to the test results, we see excellent stability of output voltages on all lines due to separate stabilization. The ripple level at the output of the unit was measured at currents +3.3V 15A, +5V 15A, +12V 50A and amounted to 48 mV, 35 mV and 98 mV, respectively, which fits into the ATX standard.

The unit efficiency test was carried out at a mains voltage of 230 V, with a reduced mains voltage, the efficiency will be slightly lower.

The efficiency of this block meets the 80 Plus Bronze standard.

Now let’s look at the heating of the elements inside the device.

The heating of the components is higher than that of modern power supplies with a resonant converter. Of the main problem areas, this is the high temperature of the output inductor, next to which the output electrolytic capacitors are installed along the + 12V line and high heat will shorten their service life, despite the quality of the components. Perhaps, due to the increased heating, the manufacturer gives a guarantee for the unit for only two years.

conclusions

The tested Enermax RevoBron 700W ED2 is made with a high-quality element base and has excellent output voltage stability, although it is equipped with a slightly noisy fan. It looks nice and comes with cables long enough to build a system in a tall case with a low power supply. In the new version of RevoBron, the manufacturer abandoned the external controller for connecting fans, which slightly affected the final cost of the product. But its price still remains at the level of solutions from less famous manufacturers with better energy efficiency. If you need a power supply from Enermax with a certificate of 80 Plus Gold, then you can pay attention to the Revolution DF series, which will cost a little more.