Basler Electric DECS-250E Digital Excitation Control System

A compact enclosed excitation system with a built-in 50, 100 or 200 Adc rectifier bridge

The Basler Electric DECS-250E provides regulation, control and protection for synchronous motors or generators in a single compact enclosure. Three models supply a maximum of 50 Adc, 100 Adc or 200 Adc of excitation current, in either a static or a rotary exciter application, so one platform covers machines that a bare controller cannot drive.

Where a DECS-250 sends a control signal to an external bridge, the DECS-250E houses the controller and a positive-forcing rectifier bridge together, which simplifies installation and keeps the cost down for a wide range of applications.

DECS-250E functions

• Bridge selection: 50, 100 or 200 ampere positive forcing rectifier bridge for the main field or exciter field
• AVR, FCR, FVR, power factor and var operating modes with true RMS metering
• Protection: 27/59, 81O/U, 32R, 40Q, 59F, 51F, field short circuit and 25 sync check; configurable protection
• Overexcitation and stator current limiting (temperature compensated), underexcitation, var and V/Hz limiting
• Auto-tuning, two PID groups, load sharing over Ethernet, optional automatic synchronizer
• Ten programmable contact inputs and nine contact outputs; AEM-2020 and CEM-2020 expansion
• Conformal coating on certain internal circuitry

DECS-250E technical specifications

Power, output and sensing

Inputs, outputs and communication

Environment and mechanical

Selecting the DECS-250E current rating

Select the style from the exciter or generator main-field requirement: 50, 100 or 200 Adc continuous, remembering the 133 Adc derating of the 200 Adc style on single-phase power. Choose control power by style letter (L for 18 to 30 Vdc, C for 90 to 150 Vdc or 90 to 132 Vac) and confirm that the operating AC voltage gives the right DC output (63, 125 or 250 Vdc). Send the generator nameplate and exciter field data and we will match the style from the datasheet chart.

Installation notes

The enclosure is IP20 and weighs 25.2 kg, so allow for wall or panel mounting and cooling clearance; NEMA 1 cabinets are available for dust control. Datasheet accessories include field flashing modules (125 Vdc or 24 Vdc), a shaft suppression module to reduce risk of damage to generator bearings, and an AC line filter in 50/100 Adc and 200 Adc versions. Setup is with BESTCOMSPlus; follow the instruction manual for the commissioning sequence.

Where the DECS-250E fits

It is aimed at synchronous machines with high field demand: large generator sets in power stations and process plants, and synchronous motors on mills, compressors and crushers. The IP20 enclosure suits air-conditioned electrical rooms and switchgear houses; the rated ambient is 60 C maximum, so keep the room within that limit in summer.

Selection and care notes

Confirm the field current and voltage of the machine before choosing the 50, 100 or 200 Adc model, and check the supply to the bridge. The enclosed design needs ventilation and protection from dust and moisture in the room, and the commissioning should include tests of the limiters and the voltage matching. Document the settings after commissioning.

Information needed for a quotation

Send the full model code, the quantity, the delivery location in Oman or the GCC, the machine or system it will control and any accessories or software needed, so that the complete package can be quoted together.

Documents and supply information

The manufacturer data sheet is attached to this page and should be read together with the project specification before a purchase is confirmed. Ratings, functions and dimensions are quoted as printed on that sheet. Lead time, stock position and certificates available with the shipment are confirmed in the quotation, and we supply to Oman and the wider GCC region for industrial, utility and building services projects.

Related Basler Electric items

Basler lists the DGC-2020 genset controller, BE1-FLEX protection, the IDP-801 interactive display panel, CEM-2020 and AEM-2020 expansion modules, field flashing and shaft suppression modules, and an AC line filter for EMI.

Frequently asked questions

What are the DECS-250E current ratings?

Three models provide a maximum of 50, 100 or 200 Adc of excitation current.

Does it include the rectifier bridge?

Yes. A 50, 100 or 200 ampere positive forcing rectifier bridge is selectable in the compact enclosure.

What is the enclosure rating?

IP20, with NEMA 1 cabinets available.

Can it parallel generators?

Yes. The datasheet lists load sharing over Ethernet and an optional automatic synchronizer.

Is Seven Star LLC a Basler Electric distributor?

No. Seven Star LLC is an independent supplier in Muscat, Oman, sourcing genuine Basler Electric products for GCC customers on request.

Documents and quotation

Manufacturer document: the DECS-250E product bulletin (SZU-11, 11-23), hosted on this page. Compare it with the instruction manual before you confirm the exact style or order code. Seven Star LLC supplies Basler Electric items from Muscat to buyers in Oman and the wider GCC; send the model, option code and quantity through the quotation form for availability. Pricing is on request, and every rating or approval should be re-checked against the current maker documents. More: Diesel Generator Spare Parts and the Basler Electric brand page.