• Number of output channels: 3
• Max. output current per channel: 5 A
• Max. output power per channel: 80 W
• Total output power: max. 188 W
• Output voltage per channel: 0 V to 32 V

The R&S HMP power supplies are primarily designed for industrial use. With two, three or four output channels and up to 10 A output current per channel, these rugged instruments are ideal for a wide variety of applications. They offer high efficiency with low residual ripple and many protection functions.

The R&S HMP power supply family consists of four models. The R&S HMP2020 two-channel power supply and the R&S HMP2030 three-channel power supply deliver up to 188 W total output power, the three-channel R&S HMP4030 and the four-channel R&S HMP4040 offer a maximum output power of 384 W. The total load can be distributed as desired over the separate channels. Depending on the model, up to 80 W or 160 W of channel power is available - in any voltage/current distribution.

Up to four galvanically isolated, floating output channels with overload and short-circuit protection are available, depending on the instrument type. The channels can be connected in series or parallel to obtain higher voltages or currents. The R&SHMP4040, for example, offers a maximum voltage of 128 V or a maximum current of 40 A.

All basic functions of the R&S HMP power supplies are directly accessible on the front panel. The rotary knob plays a key role. It is used to set the voltage, current and limit values for the various protection functions.

The channel keys light up in different colors to indicate the operating conditions of the channels. All channels can be simultaneously switched on or off with the “Output” key, which lights up white when it is "on". Active outputs light up green in constant voltage mode and red in constant current mode.

The R&S HMP power supplies offer a variety of protection functions to prevent damage to the instrument and the DUT. You can separately set the maximum current (electronic fuse, overcurrent protection/OCP) or the maximum voltage (overvoltage protection/OVP) for each channel. The output channels switch off when either of their set limits is reached. Overtemperature protection (OTP) prevents the instrument from overheating.

In industrial applications, power supplies are often installed in 19-inch racks. The R&S HZ42 and R&S HZP91 rack adapters are available for this purpose. Additional connections for all channels (including sense lines) are provided on the rear panel to simplify use in system cabinets.

The R&S®HMP power supplies can be equipped with an optional interface. Available interfaces include a dual USB/LAN (R&S®HO732), a dual RS-232/USB (R&S®HO720), and an IEEE-488 (GPIB) (R&S®HO740) interface.

All Channels Galvanically Isolated and Floating

The R&S HMP power supply family consists of instruments with two, three or four channels. The circuitry of each single channel is completely isolated from the others; there is no connection to chassis ground. This makes it easy to combine the channels to drive balanced circuitries that might need +12 V/-12 V, for example, and avoids any ground problems in complex DUTs.

Two channels can be connected together to supply balanced circuits with e.g. +12 V/-12 V.

All Channels Have The Same Voltage Range

In contrast to other power supplies on the market, the R&S HMP power supplies offer the same voltage range on all channels. You can select any channel for a specific application. Each channel can be regarded as a separate power supply. Four models in two power classes are avail- able, with two, three or four output channels.

All Channels Have Overload and Short-Circuit Protection

Even the most experienced user is occasionally distracted - so it’s good to know that since the outputs are protected against overloads and short circuits, the R&S HMP power supplies will not be damaged.

Parallel and Serial Operation

Because all channels are electrically equivalent, they can be combined in serial mode to achieve higher voltages. Up to 128 V can be achieved with the R&S HMP4040. In parallel mode, the channels can be bundled for higher current. Up to 20 A can be achieved when two channels are combined, and up to 40 A when all four channels of the R&S HMP4040 are combined.

Because all channels are electrically equivalent, they can be combined in serial mode to achieve higher voltages. Up to 128 V can be achieved with the R&S HMP4040. In parallel mode, the channels can be bundled for higher current. Up to 20 A can be achieved when two channels are combined, and up to 40 A when all four channels of the R&S HMP4040 are combined.

Constant Voltage and Constant Current Modes

Configuring and regulating the output voltage (constant voltage mode) is the standard application for power supplies. However, the R&S HMP power supplies can also be used in constant current mode, with each channel separately configurable. If the configured current level is exceeded, current limiting ensures that only the configured current can flow. The output voltage is accordingly reduced below the configured value. This prevents damage to the test circuit in the event of a fault.

Tracking and Link Functions

The separate output channels can be used as independent power sources, but their true versatility becomes evident when combined. The channels can be connected in parallel to achieve higher currents or in series for higher voltages. The convenient tracking function lets you vary the voltage on all channels in parallel. The link function for the electronic fuses makes the instrument even more versatile. The power supply can be configured to switch off all channels when any one of the channels reaches its limit value. It can also be configured so that certain channels remain active, for example to power the fan that cools the DUT. The status of the fuses and all other protection functions are always shown on the display.

The output channels can be configured in parallel to achieve higher output current, or in series for higher output voltage.

Protection Functions To Safeguard Instrument and DUT

Protection functions are common in performance power supplies with their high output power. But they are not always implemented as consistently as in the R&S HMP power supply family. For example, the limit values for all protection functions can be configured separately for each channel.

Maximum Voltage (Overvoltage Protection, OVP)

If the voltage rises above the configured maximum value, the output is switched off and the “OVP” indicator on the display blinks. Depending on the setting, the voltage configured on the instrument or the voltage measured by the instrument is used as the switching threshold for OVP.

Maximum Current (Electronic Fuse, Overcurrent Protection, OCP)

To provide even better protection for sensitive loads, each channel of the R&S HMP power supplies is equipped with an electronic fuse that can be separately configured or cleared. If a configured current level is exceeded, the af- fected output channel will be automatically switched off and a message will be displayed. The electronic fuse can be linked to other channels (FuseLink function). If a channel exceeds the maximum current level, then this channel and all linked channels will be switched off. Even the delay time of the electronic fuses can be set. With this functionality, you can adjust the behavior of the power supply so that short current spikes that occur when a channel is switched on do not trip the electronic fuse.

Overtemperature Protection (OTP)

Of course the R&S HMP power supplies have internal overtemperature protection that switches off the instrument if there is an imminent risk of thermal overload.

Modern Instrument Concept: Small, Compact and Quiet

Universal power supplies need to fulfill a variety of requirements. For instance, they must work reliably in countries with unstable power grids. The primary transformer in the R&S HMP acts as a lowpass filter to maintain stable operation.

Power supplies should be small and compact. The secondary switching regulator makes the R&S HMP extremely efficient. It reduces weight and size, and the regulated fan usually runs at low speed or shuts off completely, which results in low noise.

Power supplies should provide stable output voltages/cur- rents with low ripple. This is realized by using linear control circuitry for stabilization.

Intuitive to Use

All basic R&S HMP power supply functions can be operated directly via keys on the front panel. It is only necessary to use the menu level for special functions that are needed less frequently.

Simply press the “Voltage” key, select an output channel and use the rotary knob or arrow keys to adjust the output voltage in steps as small as 1 mV. You can similarly set a constant output current with a resolution as fine as 0.1 mA, depending on the model and the current range. On the R&S HMP4030/HMP4040 instruments, you can also use the numeric keypad to enter values. If you need to set several channels at the same time, for example to increase the output voltage from ±12 V to ±15 V, simply press the “Track” key and select the two channels for the positive and negative voltages. Now you can use the rotary knob to symmetrically adjust the two voltages. Activating and deactivating the electronic fuses is just as easy - simply press the “Fuse” key and the channel key.

Color Coding of Operating States

All settings and operating conditions, including the output power and the status of the protection functions, are shown on the display and indicated by the colors of the illuminated channel keys. The colors of the illuminated keys indicate the different operating conditions:

• Active channel in constant voltage mode: green
• Active channel in constant current mode: red
• Channel in setting mode: blue

The “Output” key lights up white when the selected output channels are connected to the load.

EasyArb Function For All Channels

Some applications require you to vary the voltage or the current during a test sequence, for example to simulate different charging conditions of a battery. The EasyArb function provides a convenient solution. It lets you program time/voltage or time/current sequences, either manually via the user interface, or via the external interfaces.

EasyArb can be used for separate channels or for all channels. Up to three complete arbitrary curves with up to 128 points can be saved in the internal memory and retrieved when needed.

Frequently used settings can be saved and retrieved using the “Store” and “Recall” keys.

All settings and operating states are clearly visualized. Constant voltage mode is indicated by a green key, constant current mode is indicated by a red key. The key color changes to blue in setting mode.

Tailored For Use In Labs and System Racks

Performance power supplies are designed for higher output power than standard instruments. They must be stable and at the same time provide the required accuracy and speed, regardless of whether they are used on the lab bench or integrated into a production test system.

Remote control functions and rack adapters are essential in system applications. Access to rear panel connections, and above all compact design, are key factors for use in test systems.

The R&S HMP power supplies fulfill all these requirements - in particular the R&S HMP4040, which uniquely combines four electronically equivalent high-performance channels in a compact package.

Sense Function For More Stringent Accuracy Requirements

There is often a significant voltage drop over the connection leads, especially in applications with high current consumption. Since power supplies usually maintain a constant output voltage, the voltage on the DUT will be lower than the voltage displayed on the instrument. The sense function compensates for this voltage drop over the supply leads. The voltage actually present at the load is measured by an additional pair of sense lines, and this value is used to regulate the voltage directly at the load. The R&S HMP power supplies provide separate sense lines for each output channel.

Connections on front and rear panels

The safety sockets on the front panel of the R&S HMP power supplies are designed for 4 mm banana plugs. Additional connections for all channels (including sense lines) are provided on the rear panel to simplify use in rack systems.

All instruments in the R&S HMP family can be remotely controlled for use in test systems. The Standard Commands for Programmable Instruments (SCPI) scripting language is used. The following interfaces are available:

The R&S HO732 dual interface with ports for USB and LAN is available as an option. This interface option can be installed instead of the standard R&S HO732 interface.

The R&S HO720 dual interface with ports for RS-232 and USB is available as an option. This interface option can be installed instead of the standard R&S HO732 interface.

The R&S HO740 interface with a GPIB (IEEE488) port is also available as an option. It can also be installed instead of the standard R&S HO732 interface.