How PECO Powersaver Works
One unit, installed at a single point in the distribution system, serving the whole facility. No change to any connected equipment.
One Point in the System
PECO Powersaver is connected in series between the main circuit breaker and the sub-distribution boards. One unit therefore serves the entire distribution system downstream of that point.
Nothing beyond the electrical room changes.
Individual equipment, sub-panels, control systems and metering remain exactly as they are.
The rating of the PECO unit is normally matched to the rating of the facility transformer, so that the whole distribution system is covered by a single installation.
Five Steps, Continuously
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01
Three-Phase Input
Power arrives from the main circuit breaker at 415 V, three-phase three-wire, with an input tolerance of ±7 %.
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02
Saving Path
Under normal operation the automatic transfer switch connects the Harmonic Energy Recycling Transformer into circuit. This is the position the unit holds for the life of the installation.
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03
Through the Winding
Load current passes through the zig-zag main winding and the reverse auxiliary winding. The two are tied at both ends, so the series path adds very little resistance — and the zig-zag interconnection couples the three phases magnetically rather than treating them independently.
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04
Low-Heat Transformation
The auxiliary winding establishes the fixed 4 % voltage difference. Because it is bonded to the main winding at both ends, it carries that current at lower resistance than its own conductor would allow — so added resistance, and added heat, stay low.
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05
Supply to the Facility
Output is delivered to the sub-distribution boards at approximately 96 % of input voltage — 398.4 V from a 415 V supply — within the range permitted by EN 50160 and IEC 60038.
No adjustment, no calibration and no operator intervention is required at any stage.
What Installation Involves
PECO is installed into a live distribution system. The work is straightforward, but it requires a planned outage of the main distribution — and that is the part worth planning carefully.
Before the day
We review the single-line diagram, transformer rating, voltage, frequency, maximum load current and available space before anything is ordered. Cable and busbar sizes, terminal types and the position of the unit are confirmed at that stage.
Foundation and access work is completed in advance. The unit is installed upright, on a flat surface with adequate load-bearing capacity, with clearance at front and rear for door operation and inspection.
On the day
The main circuit breaker is switched off. Input terminals are connected to the supply side and output terminals to the load side. Every bolted joint is torqued and marked. Grounding is verified against the applicable standard, and each phase is checked before power is restored.
The duration of the outage depends on cable and busbar work at the site, not on the unit itself. It is estimated during technical review and agreed with the facility in advance.
Commissioning
With the loads still disconnected, the control circuit is energised and the transfer switch is operated through both positions to confirm correct indication. The unit is then left in the Saving position, control is set to automatic, and loads are restored last.
Ventilation is verified against the thermostat setting, and the digital meter is checked against measured values before handover.
Site requirements
- Indoor installation
- IP 42
- Standard electrical switchgear room ventilation
- Flat surface with adequate load-bearing capacity
- Front and rear clearance for door access
- Installation by qualified electrical personnel
Two Positions, One Switch
The automatic transfer switch selects between two paths.
Saving
Input → Harmonic Energy Recycling Transformer → Load
Normal operating position.
By-pass
Input → Direct path → Load
The transformer is out of circuit. The facility is supplied directly, exactly as it was before installation.
Automatic transfer
The EOCR monitors load current. If the preset overload condition is detected, its contact operates the control circuit, which commands the transfer switch to move the load to the By-pass path. This is a protective function and operates under load.
Manual transfer
Deliberate transfer between the two positions — for maintenance, or for measurement — is carried out at no load, during a window scheduled with the facility. Loads are disconnected, the switch is operated, and loads are restored last.
The installation can be reverted at any time.
Because the By-pass path restores the original supply arrangement exactly, the facility can be returned to its pre-installation condition without any effect on connected equipment.
See how savings are measuredWhat Happens Afterwards
Very little, by design.
The transformer has no consumable parts, no firmware and no settings that drift. Routine attention consists of visual inspection, keeping the enclosure and ventilation clear, checking bolted joints, confirming the fan responds to its thermostat setting, and verifying input and output voltages.
Intervals are set according to the facility’s own electrical maintenance policy rather than prescribed by us.
Warranty
- Harmonic Energy Recycling Transformer
- 3 years
- Switching and protection components
- 1 year
From the date of installation.
Start with a Technical Review
Suitability, capacity, connection arrangement and expected outage duration are all confirmed at the review stage — before any proposal is made. Send your single-line diagram and transformer rating to begin.