TMG-2500 2500 kVA 10/0.4 kV transformer (S13-M-2500)

TMG-2500 (S13-M-2500) technical data

Rated current and permissible load

Losses, efficiency and comparison with amorphous SH15

The amorphous-alloy core of the SH15 cuts the no-load loss by 51 % compared with the S13. For one 2500 kVA transformer this saves about 8147 kWh per year, because no-load loss is present the whole time the transformer is energised, regardless of the load.

Where a 2500 kVA transformer is used

The TMG-2500 is typically installed where the load at one 0.4 kV point of supply exceeds what a 1600 kVA unit can carry: large industrial plants, data centres and major water-utility pumping stations. It usually feeds the site's main 0.4 kV switchboard, which in turn supplies workshop distribution boards, data halls or groups of pump sets. For critical consumers the substation is typically built with two transformers, so that the essential load can be transferred to the second unit when one is taken out of service.

• Unit substations in large industrial plants
• Data centres
• Large water-utility pumping stations
• Energy-intensive production: metalworking, chemicals, building materials
• Shopping and logistics centres with refrigeration
• Two-transformer substations with sectioned 0.4 kV busbars

How to choose a TMG-2500

Size the TMG-2500 by the calculated load: 70–80 % loading corresponds to 1575–1800 kW at cos φ 0.9, against 2250 kW at rated power. If the calculated load, including expected growth, stays within 70–80 % of 1600 kVA, the TMG-1600 is sufficient, costs less and has a lower no-load loss. The S13 series ends at 2500 kVA, so a load beyond one TMG-2500 is split between two transformers feeding separate 0.4 kV busbar sections with a bus-tie breaker; this layout also gives redundancy for data centres and pumping stations.

The TMG-2500 is available with Yyn0 or Dyn11, and the load loss is the same 21200 W for both. Dyn11 copes better with unbalanced single-phase loads and with third harmonics from server and other single-phase switch-mode power supplies, and it gives a larger single-phase fault current, which makes it easier to verify protection on long 0.4 kV feeders. For data centres and sites with a large share of single-phase non-linear load Dyn11 is therefore the usual choice. Yyn0 remains the traditional option where the neutral is lightly loaded, for example at a pumping station with three-phase motors.

The choice between S13, amorphous SH15 and energy-efficient S-M-NX1 depends on the load profile. No-load loss runs 8760 h a year: 1830 W for the S13-M-2500 against 900 W for the SH15-M-2500, which is 51 % less, with identical load loss. When the average loading stays below half of rated power, as in a two-transformer redundant scheme, the SH15 advantage grows; note that the SH15 is built with Dyn11 as standard, while with a three-phase three-limb core the Yyn0 vector group can also be supplied on request, so state it in your inquiry if you need it. Where one transformer runs at high load around the clock without redundancy, as in a three-shift plant, compare the S13 with the S-M-NX1, which meets energy-efficiency grade 1 to GB 20052-2020 and has lower losses.

Compact substation with a 2500 kVA transformer

The 2500 kVA transformer is also supplied as part of a compact substation: YB European-type substation (BKTP / GKTP), up to 2500 kVA. The substation is assembled and tested at the factory, so the site work mainly comes down to setting it in place and connecting the cables.

Other TMG (S13) ratings