Pro 2 Power Supply

The constant current time of the Pro 2 Power Supply is currently between 15 and 20 seconds.

Parallel operation of Pro 2 Power Supplies is possible in “Active Droop” mode if the parallel connection is made on external rail-mount terminal blocks and the lengths and cross-sections of the cables to the load are identical. If one power supply unit fails, and the output current of the remaining intact Pro 2 Power Supply is not sufficient for the load, an overload occurs. If the entire load is at most 150 % of the nominal current, the PowerBoost function activates, and switch-off occurs after about 5 seconds, but not earlier. If the entire load is at most 110 % of the nominal current, switch-off occurs after about 15 or 20 seconds, but not earlier, in constant current mode. Incidentally, the mean time between failures (MTBF) of our Pro 2 Power Supplies is 1,000,000 hours – the whole lifespan of a machine.

To put the Pro 2 Power Supply in circuit breaker mode, the configuration software or SPS function blocks are required initially. In this step, you can directly specify how the power supply unit should be reset:

• Via the function keys on the front (hold both keys down for three seconds),
• Via the digital input,
• Via configuration software over the communication interface or
• Via a higher-level controller through the communication module.

The single-phase Pro 2 Power Supplies do not capture the input voltage or input current. However, assuming constant input voltage and a known efficiency value (according to the datasheet), the current input currents can be calculated: efficiency = (Uout * Iout) / (Uin * Iin) Iin = (Uout * Iout) / (Uin * efficiency)

The number of Pro 2 Power Supplies of the same type connected in parallel is not initially limited, as long as the parallel connection is established to external rail-mount terminal blocks and through cables of the same impedance to the rail-mount terminal blocks. Parallel operation of different versions – for example 10 A and 20 A power supplies – is also possible in the “Active Droop” operating mode (factory settings).

In constant current mode (latch mode), the Pro 2 Power Supply supplies constant output current of about 110 % of the nominal current for about 15 s if the output is overloaded. The output then switches off and must be restarted by the user. Constant current mode must first be activated via the configuration software or via SPS function blocks. In this step, you can directly specify how the power supply should be restarted: - Via the function keys on the front (hold both keys down for 3 seconds), - Via the digital input, - Via configuration software over the communication interface or a higher-level controller through the communication module.

In Germany and the rest of Europe, three-phase power supplies are often used to provide 24 VDC power to control cabinets. The load can be evenly distributed among the three phases, the N conductor is not loaded, and power supply operation can be maintained even if one phase fails.

Yes, in the range of 30 % of the nominal current and above, you are free to set the trip current to any value. Furthermore, you are also free to set the tripping time of our Pro 2 Power Supplies between 100 ms and 5 s.

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.

This function can be enabled for safety reasons in certain applications. For example, after a mains failure, it may be necessary for the power supply to not start up automatically, but rather to require manual reset. This prevents the equipment from ending up in an undefined state. In existing applications, safety relays with downstream contactors are often used for this purpose. The “Digital Output Remains Switched Off” function of the Pro 2 Power Supplies eliminates the need for such safety relays.

As a general rule, the DC OK contact only depends on the voltage, not the load situation in the nominal range. The short circuit responds to an overload or short circuit, as well as a voltage below the threshold. For a load-dependent effect on the DC OK contact, the custom warning threshold must also be configured accordingly.

No, direct parallel connection of Pro 2 Power Supplies on the terminals on the output is not allowed. First of all, the difference in cable resistances to the load leads to asymmetries that cannot always be compensated by adjusting the output voltage. Secondly, the 831 Series female connectors can only withstand loads up to 40 A; parallel connection would lead to a higher current load and exceed this limiting value.

You can access the Pro 2 Power Supply settings through the communication module of the higher-level controller. The configuration software allows all configurations to be saved conveniently on a computer.

Not yet, but this modification is planned for an upcoming firmware update.

The Pro 2 Power Supplies can be configured in such a way that the digital signal output toggles if a load current value set by the customer is reached. Setting a load range with an upper and lower limit is not possible (yet).

If you select these options, the Pro 2 Power Supply communicates via the 2789-9080 Communication Module. The higher-level PLC then assumes control of the digital input and digital output.

Due to their high efficiency, the Pro 2 Power Supplies have low intrinsic heat generation. You can achieve optimal heat dissipation by installing the power supplies upright on the DIN-rail. In this orientation, cool air can flow in from below, and the heated air can escape upwards unimpeded. There should be at least 5 cm of clearance between the ventilation grille and other devices or cable ducts. At temperatures above 60° C, a derating of 3 % per kelvin must be taken into account.

No, the buttons of the Pro 2 Power Supplies are not locked upon delivery or when the module is inserted. The button lock feature must be configured manually.

The Pro 2 Power Supplies do not capture and store data over a long time period. However, if the Pro 2 Power Supply is connected to a computer, smaller measurements can be recorded. To do this, navigate to the “Measurement Recording” tab in the configuration software and click Start. The data is stored in a CSV file on your computer.

We cannot allow replacement of original components of Pro 2 Power Supplies. Opening the device invalidates all warranty claims. Furthermore, we would no longer be able to guarantee electrical safety or compliance with EMC limiting values.

Besides a configurable input and output for digital signals and the USB service cable that can be used on the front side, snap-on communication modules are available. For example, the 2789-9080 module supports IO-Link specification 1.1 and allows continuous fieldbus communication. Thus Pro 2 Power Supplies already support predictive maintenance within the control cabinet.

The storage temperature for our Pro 2 Power Supplies is between −40 and +85° C.

We gave a great deal of thought to this issue before determining the specifications for this power supply. At nominal output voltage of 960 W or higher, a broad input range from 90 to 264 VAC would have many disadvantages such as size, lower efficiency, higher power loss, shorter service life and, last but not least, higher costs. Therefore, we chose an input voltage range of 180 … 264 VAC, which also allows operation between two phases in networks with voltage to the neutral conductor of 100 VAC or 110 VAC.

According to the datasheet, the three-phase Pro 2 Power Supplies, the 2787-2347 and 2787-2348, have a DC input voltage range from 480 to 780 VDC. If higher DC input voltage is needed, e.g., 800 VDC, please contact Support to discuss additional conditions for use.

The input-side protective circuit of the Pro 2 Power Supplies consists of gas-filled surge arresters; they can be disabled with a screw on the outside of the housing to avoid interfering with insulation measurements.

Our Pro 2 Power Supplies are protected against short circuit on the output side and can output a warning via the configuration software, for example. Depending on the configuration, the Pro 2 Power Supply responds either with a TopBoost of 600 % for 15 ms or a PowerBoost of 150 % for 5 s. The power supply then provides 100 % to 105 % of the nominal current on the output until the internal transformers switch off for safety reasons. If constant current mode is selected in the configuration, the power supply starts up automatically after cooling off. If the “Latching Shutdown after Thermal Overload” function has been selected in the configuration instead, the power supply does not start up automatically, but instead waits for configuration from the user or a signal change on the digital input. You can find more information on the overload behavior, as well as current/voltage/time diagrams, here.

You can find the expected lifespan of the electrolytic capacitors, the so-called “CAP lifetime,” and further information on individual components in the manual for the corresponding Pro 2 Power Supply.

Versions with coated PCBs are in the pipeline; please contact Support for details.

At 70 mV peak-to-peak, the Pro 2 Power Supply has a low ripple factor at nominal load by default. When the power supply is used at partial capacity, the ripple factor is somewhat lower.

In accordance with DIN EN 60068, the vibration resistance of the Pro 2 Power Supply is 1g, and the shock resistance is 15g.

Within the “Pro 2 Power Supply” family, the pin assignment of the MCS connector was designed to be uniform. Unfortunately, this means the pin assignment differs across series. In this specific case, the pin assignment differs because the plug of the 2787-2146 Pro 2 Power Supply has two plus potentials and three minus potentials, but the plug of the 787-1602 Classic has two plus potentials, two minus potentials and a DC OK contact. In future, the potential assignment will also be indicated on the front of the Pro 2 Power Supply housing to prevent the possibility of errors due to connection of the wrong female connector.

The constant current overload currently limits the output current to about 10 % of the nominal output current for 15 s before the Pro 2 Power Supply switches off. After that, there are two options: - In constant current locking mode, the power supply starts up automatically. - In Latch mode, the power supply does not start until the user confirms manually.

No, all Pro 2 Power Supplies currently operate with a nominal output voltage of 24 VDC. Devices with nominal output voltages of 12 VDC and 48 VDC will follow. You can find the right power supplies for 15 VDC applications in our portfolio, such as: - 787-1631 Classic Power Supply with an adjustable output voltage range from 11.5 to 15 VDC - 787-1001 COMPACT Power Supply with an adjustable output voltage range from 10.5 to 18 VDC

Yes, all our Pro 2 Power Supplies are certified per UL standards 61010-2-201 and 61010-1.

A version of the 24 VDC Pro 2 Power Supply will be available with ATEX/IECEx approval. Please contact our Support department for details.

A Pro 2 Power Supply cannot meet the SIL 2 requirements on its own, but generally only in conjunction with a second power supply and a redundancy module. SIL 2 approval for this device combination is under review. In such cases, our support team will be glad to provide further assistance.