Power and Energy Systems Selection Guide
Power and energy systems consist of UPS, regulator, PDU, charging station and charging socket groups; the choice is made according to needs such as supply during an outage.
This guide explains what to look at when choosing products in the Power and Energy Systems category.
Which product group for which need
- Supplying the load during an outage: UPS uninterruptible power supplies. Line interactive UPS models are listed in ratings such as 600 VA, 1500 VA and 3000 VA; online UPS models in ratings such as 1 kVA, 10 kVA, 20 kVA and 160 kVA, as single-phase and three-phase.
- Regulating voltage: under Regulators there are Siel servo-controlled single-phase (1ph/1ph) and three-phase (3ph/3ph) voltage regulators.
- Distributing power inside a cabinet: PDU power distribution units; of the Schneider Electric Easy PDU metered models, the 1U one has C13 outlets and the zero-U ones have C13 and C19 outlets.
- Electric vehicle charging: Charging stations are 7.4 kW, 11 kW and 22 kW AC models from the Schneider Charge and Charge Pro series. The charging sockets category contains Bemis cabled CCS2 DC charging sockets.
- Off-grid energy: Portable power stations and the 100 W and 200 W OffGrid panels in the solar panels category. Rooftop and ground-mount power plant panels are not in this list.
- 24 V output: the isolation transformers category lists Bemis transformers with 24 V output, 100 W and 200 W ratings and a socket.
What to look at when choosing a UPS
- Topology. In a line interactive UPS the load is normally fed from the mains; in an online (double conversion) UPS it is fed continuously from the inverter.
- Power. The VA or kVA value in the product name is apparent power; some names also give the W value (such as 2200 VA and 1320 W). The connected load must stay below both limits.
- Phase configuration. The 1ph/1ph, 3ph/1ph (3:1) and 3ph/3ph (3:3) notations give the number of input and output phases.
- Battery. Some names include the note with battery or without battery; the battery module and the empty battery cabinet are separate items.
- Form and accessories. There are tower, cabinet and rack-tower housings; accessories such as network cards and parallel kits are in the same list as the UPSs.
You can make a preliminary check of the load current with the current and fuse calculation from active power tool; sizing the UPS and the supply line belongs to the project calculation.
Choosing a servo regulator
A servo regulator is an electromechanical regulator that monitors the output voltage and moves the slider or tap of an autotransformer with a servo mechanism. In selection, check the phase configuration (single-phase or three-phase), the kVA value that covers the total load (the list includes ratings such as 3.5 kVA, 15 kVA, 60 kVA and 150 kVA), the allowance to leave for inrush current with motor loads, and whether the voltage deviation on the mains stays within the input range of the device. Because the correction is mechanical, there is a response time; for loads sensitive to momentary voltage dips, a UPS is considered.
AC station and DC socket in electric vehicle charging
An AC charging station supplies alternating current to the vehicle; the conversion to direct current is done in the vehicle's onboard charger. For this reason, the charging power is limited by the vehicle's onboard charger and the supply capacity of the facility as much as by the station. In product names, 7.4 kW models appear as single-phase (1P+N) and 11 kW models as three-phase (3P+N). Models marked T2S have a shuttered Type 2 socket, and models marked Cable or Att Cable have a fixed cable; some names also give the cable length. The anti-tripping modules of the Schneider Charge series are in the charging accessories category.
CCS2 is a DC charging connection with two direct current contacts added to the Type 2 connection. The 150 A, 250 A and 400 A sockets in the list come with a cable open at one end; they are components to be connected to a DC charger, not a charger on their own.
Brands in this category
- Schneider Electric: APC Back-UPS and Easy UPS models, Easy PDU, Schneider Charge charging stations, OffGrid portable power products.
- Siel: line interactive and online UPSs and servo voltage regulators.
- ABB: double conversion online UPSs; the product name contains only the order code.
- Bemis lists 24 V transformers and CCS2 charging sockets, and Cata lists portable power stations.
Order notes
- Products are sold per piece. PDUs and some of the UPSs are listed as made-to-order; for these products the lead time is confirmed before ordering.
- For ABB UPSs, the power and housing form are written not in the product name but in the product properties (apparent power output, form).
- Since the UPS list also contains accessory items, check the product type before adding to the cart.
- You can reach the product directly by typing the manufacturer code (such as E3SUPS20K3IB, EVH5A11N2C5, EPDU2016M) into the search.
Comparison and selection table
| Selection Criterion | Online / Line-Interactive UPS | Servo / Static Voltage Regulator | Industrial Power Supply (SMPS) & Inverter |
|---|---|---|---|
| Primary Function | Zero-transfer battery backup + clean sine-wave AC | Stabilizes sagging/surging mains to 230/400 V AC | Converts 230/400 V AC to regulated 24 V / 12 V DC |
| Outage Backup | Yes (internal/external battery bank autonomy) | No (corrects voltage while mains is present) | SMPS runs on AC mains; inverter converts DC battery to AC |
| Capacity Rating | VA / kVA (1 kVA single-phase to 200+ kVA three-phase) | kVA (single-phase or three-phase servo/static) | Watts / Amps (e.g. 24 V DC 2.5 A / 5 A / 10 A / 20 A) |
| Typical Application | Servers, medical gear, PLC/SCADA & critical loads | Plants with unstable grid voltage, CNCs & elevators | Control cabinets, PLC/sensor rails & off-grid power |
Frequently asked questions
What is the difference between an online UPS and a line interactive UPS?
In a line interactive UPS the load is normally fed from the mains; when the voltage sags or rises a stepped autotransformer makes the correction, and in an outage the inverter takes over. In an online, that is double conversion, UPS the load is fed continuously from the inverter and no transfer switching is needed at the moment of an outage. For this reason, online is the usual choice for loads that are sensitive even to a brief transfer, such as servers and process control, and line interactive for office computers and network devices.
Why does a UPS name give two separate power values, VA and W?
VA shows apparent power and W shows active power; the ratio of active power to apparent power is the power factor. The UPS's VA value is limited by the maximum permitted current and its W value by its power handling capacity, and neither limit may be exceeded. The total active power of the devices connected to a UPS labeled 2200 VA and 1320 W must stay below 1320 W, and their total apparent power below 2200 VA. The nameplate values of the devices are the basis for the calculation.
What do 3:1, 3ph/1ph and 3ph/3ph mean in a UPS name?
This notation gives the number of input and output phases. 1ph/1ph is a UPS fed from a single-phase mains and giving a single-phase output. 3ph/1ph or 3:1 is fed from a three-phase input and gives a single-phase output; it is used when the load is single-phase but its power is large. 3ph/3ph or 3:3 is the model with both a three-phase input and output, selected for feeding three-phase loads or large distribution panels.
What does a UPS without battery mean?
The note without battery shows that the UPS is delivered without a battery bank; a battery must be connected for it to supply the load in an outage. The battery bank is selected separately according to the desired backup time and the load; in the list the battery module and the empty battery cabinet are separate items. The version of the same model with battery may be listed as a separate product. The battery type and quantity are determined from the manufacturer's data.
How do you choose between a 7.4 kW, 11 kW and 22 kW charging station?
First look at the supply of the facility: in the Charge Pro product properties, the 7.4 kW value is given with 32 A and 230 V, the 11 kW value with 16 A and 400 V, and the 22 kW value with 32 A and 400 V; the first is a single-phase supply and the other two are three-phase. The second limit is the vehicle: in AC charging the conversion is done by the vehicle's onboard charger, so the vehicle will not draw more than its own onboard charging power even if the station is more powerful. The third step is verifying with the project that the contract power and the line can carry this load.
What is the difference between W and Wh in a portable power station?
W shows the power the station can deliver at one time; Wh shows the energy it stores. The total power of the devices to be connected must not exceed the W value. The run time is found roughly by dividing the Wh value by the load power; because of conversion losses, the actual time falls below this result. In the list, some models have the capacity in the name (332 Wh, 517 Wh, 738 Wh) and some the output power (300 W, 2500 W); look at both values when comparing.