Supplying 3.No  ABB 294KW 1007 r/min Generators & Overhaul of Comelor Gearboxes


Renewable Energy - Hydro Power



JJ Loughran was asked by our customer to look at an existing hydro power application, the customer wanted all three generators onsite upgraded from existing Alconza units which were manufactured in 1996 to newer more efficient units, they also required a full overhaul of all three Comelor Gearboxes, which were exhibiting wear and thus excess noise and vibration.


The Solution: 

  • JJ Loughran went to site and carried out a site survey with our electrical and mechanical engineering teams, to find the best and most efficient solution to the problem.
  • Working closely with ABB we specified and supplied three new ABB Generators which would require the least amount of mechanical disruption on site, but maximise electrical efficiency and reliability with an ABB three year warranty as standard.
  • Original Alconza Generators had an output of 469 Amp at 1011 RPM, the output of ABB generators were higher at 508 Amps @ 1007 RPM, nearly a 40 Amp increase per generator @ full speed, which is a significant increase in output for our customer, resulting in an substantial increase in revenue.
  • The Comelor gearboxes were too large to overhaul onsite and as a result had to be removed to JJ Loughran’s main engineering facility, our mechanical and electrical engineering teams assisted our customer in the safe disconnection and removal of equipment on site.
  • JJ Loughran successfully carried out the full overhaul of all three Comelor gearboxes, and supplied three new ABB new generators.
  • All works were carried on time and within budget.


ABB Generator Details:

JJ Loughran specified and supplied the following three ABB Generators with the following modification codes

Generator type code


M3BG 355SMC 6

Duty type



Temp. rise


Class F

Connection of stator winding



Rated output


294 kW



415 V



50 Hz



1007 r/min

Load characteristics

Load %

Current A

Efficiency %

Power Factor

















294kW Drawing.pdf

294kW Generator Application Data Sheet.pdf


               Overhauling one of the 308KW Comelor gear units

Gearbox overhaul Details:

JJ Loughran dismantled the Comelor gearbox in our engineering workshop and carried out a full inspection, informing the customer of our findings.

We then listed all required bearings, seals and other ancillary parts which were required for the repair and overhaul of the units.


The following works were carried out:

  1. Fully testing & inspecting in workshop of original gear units with original generators to check for vibration prior to dismantling.
  2. Removal of coupling/ dismantling gearboxes into individual parts.
  3. Cleaning and inspection of all parts
  4. Removal of all old bearings and seals, checking for wear or damage.
  5. Detailed inspection of gear teeth
  6. Functional tests of pressure, level & temperature sensors on units
  7. Fully cleaning gearbox housings and removal of all traces of oil and contaminants
  8. Refitting new bearings (SKF) and seals    
  9. Reassembling gear units and refit coupling
  10. Pressure testing gear units for oil leaks
  11. Test running gearboxes to check correct operation
  12. Cleaning unit & Painting to match ABB paint specification
  13. Once the units were delivered back to site, JJ Loughran engineers helped to install and commission all equipment as necessary.  



October 4,2017