
Piller UNIBLOCK™ UBTD+
UNIBLOCK™ UBTD+ combines a rotary UPS and a diesel engine in one integrated unit. The load is normally fed from the utility through an isolating coupling choke; during an outage the energy store keeps the machine running while the diesel engine starts and takes over the load through a free-wheel clutch.
- Data centres needing high power per machine
- Hospitals and infrastructure where fault clearing and selectivity matter
- Industry with motor loads and large load steps (Piller states 100 % step loads)
Technical data
| Manufacturer | Piller |
| Type | DRUPS |
| Power | 500–2700 kW |
| Parallel | Up to 40 MW |
| Efficiency | Up to 97 % with energy store connected |
| Energy store | Battery or POWERBRIDGE™ |
| Voltage | Low and medium voltage |
| Cooling | Air or chilled water |
| Service life | More than 20 years |
Source: www.piller.com; www.piller.com.
Technology
How it works
At its heart is the UNIBLOCK™ machine, where motor and generator windings share one stator and one brushless rotor. The result is a compact machine with low sub-transient reactance – meaning low harmonic distortion and strong ability to clear downstream short circuits.
Together with the machine, the coupling choke acts as a bi-directional filter: Piller states 99 % harmonic isolation between load and utility, compensation for voltage sags down to 50 % without disconnection, and protection against brownouts to −30 % without using the energy store.
Diesel start can be delayed from seconds to minutes, so short disturbances are ridden through without an engine start. With POWERBRIDGE™, Piller states typically three times longer bridging time than other UPS solutions.

Application
Where it fits
- Data centres needing high power per machine
- Hospitals and infrastructure where fault clearing and selectivity matter
- Industry with motor loads and large load steps (Piller states 100 % step loads)
- Sites where UPS and standby power should be the same machine
Versions and options
- Containerised version, factory-built and ready to connect
- Water-cooled version with its own heat exchanger on the building chilled water
- Medium-voltage solutions
- Isolated parallel (IP bus) configuration

Service
Operation and maintenance
Piller states that nothing in the standard design requires off-site refurbishment, that there are no power capacitors or fans to replace periodically, and that the UNIBLOCK™ machine life easily exceeds 20 years.
A rotary plant should always be load-tested at commissioning – stepped load, utility failures and transfer to engine.

Other models from Piller
Read more at Bluecircle
Norwerk’s partner Bluecircle has in-depth pages on the topic.
Do you have a project or a system that needs service?
Send us the load, required autonomy and voltage level – or describe the task. We will come back with a solution sized for your operation.