Pro Power Supply

The three-phase Pro Power Supplies can also be operated on two phases straightforwardly. The full nominal output current can be drawn from the two phases; the TopBoost function, which supplies an additional 60 A for 50 ms, is also fully available.

The 787 Series Power Supplies use a transformer with safe electrical isolation. Therefore, it is possible to ground the SELV (safety extra low voltage) power supplies on the output side and create protected extra low voltage (PELV).

In the event of overload, fuse mode adjusts the current of the power supply to a very low value, while simultaneously reducing the voltage (typically 10 % of the nominal current). This reduces the power of the Pro Power Supply in the event of error and protects the cables connected to the power supply and the load against heating. Many customers do not implement secondary side fuse protection. In the event of error, the power supply should not continuously supply 110 % of the nominal current to the cables, but rather only reduced current (for cable protection). The control unit, with its display and interface, also remains active, and fault messages are output. With a hiccup, that would not be the case.

Single-phase power supplies are used, for example, in decentralized automation if three phases are not available. In Asia, entire control cabinets are powered by single-phase supplies even at high power.

TopBoost serves to rapidly and reliably trip circuit breakers. The Pro Power Supplies can use this function under all conditions in two-phase operation and with the lowest input voltage. The PowerBoost function has the following limitations: In three-phase operation at 340 to 550 VAC (as indicated on the datasheet): - 10 A/20 A device: 100 % - 40 A: 50 % In two-phase operation at 340 to 550 VAC: - 10 A device: max. 50 % - 20 A-device: max. 25 % - 40 A device: PowerBoost cannot be used The primary reason for the limitation on the PowerBoost function is the internal network input fuses, which are designed for the maximum current during normal operation. If one input phase is missing, the current through the remaining two input cables increases. In three-phase operation with minimum input voltage, the values are: - 10 A device: nominal current per phase: 0.6 A; with PowerBoost: 1.1 A; integrated fuse: 1.6 A, time-delay fuse - 20 A device: nominal current per phase: 1 A; with PowerBoost: 1.9 A; integrated fuse: 2.5 A, time delay fuse - 40 A device: nominal current per phase: 2 A; with PowerBoost: 2.9 A; integrated fuse: 3.2 A, time delay fuse

The 787-878/001-3000 Pure Lead Battery Module contains special EnerSys Genesis G13EPX batteries. The charging time is about eight hours with a charging capacity of 80 % and charging current of 1 A and 24 hours for full capacity and 1 A charging current. The 787-878/001-3000 Pure Lead Battery Modules also allow higher charging currents in connection with the 787-915 Charger/Controller, e.g. 4 A. Rapid charging is then possible to about 80 % within two hours. However, a full charge still requires 12–16 h, since the charging current decreases when a certain voltage value is reached.

For lead batteries, lead gel batteries and AGM batteries, the recommended charging current is 10 % of the capacity. For example, if the capacity of the battery is 13 Ah, our recommendation for the charging current is 1.3 A. Higher charging currents can cause excess temperatures in the battery. With the 787-1675 and 787-875 UPS units, the maximum possible charging current is 1 A. With the 787-915, charging currents of 1 A / 2 A / 3 A / 4 A are possible and can be adjusted via DIP switch. In connection with pure lead batteries such as the 787-878/001-3000 module, any of these charging currents can be used.

The mean time between failures (MTBF) of the Pro Power Supply is over 500,000 hours, in accordance with IEC 61709 (SN 29500) with nominal load and a surrounding air temperature of 40 °C.