Power Generation

Choosing oil for a generator set in Iraq

Generators carry an enormous share of the electricity used in this country — neighbourhood sets, telecom towers, factories, hospitals, cold stores and oilfield camps. Almost all of them run long hours on locally available fuel, which makes the selection logic different from a truck.

Step one: what does the engine burn?

• Diesel with high sulphur (above 1000 ppm) — the normal case in Iraq. PWR XTB 15W-40 and 20W-50, or PWR XTB II 15W-40 where extended drains and tighter deposit control are wanted. PWR ECO R2 XTB 15W-40 is the same performance on re-refined base oils. Sulphur becomes acid in the crankcase, and in an engine that runs continuously it does so far faster than in a truck that stops every evening. The reserve alkalinity and acid control in the XTB range is the whole reason to specify it over an ordinary truck oil, however good that oil's API rating looks.
• Diesel monograde duty — PWR SUPER 40, an SHPD monograde for diesel power-generation units where the engine builder specifies a straight grade.
• Distillate fuel, biodiesel or LNG on medium-speed engines — PWR SUPER LM 40, a high-alkalinity, low-ash, phosphorus-free, zinc- and chlorine-free oil for heavy-duty shore and offshore installations.
• Natural gas — PWR NATGAS SP 40, a low-ash oil for stationary natural gas engines, naturally aspirated or turbocharged, suitable for catalyst-equipped systems and exceeding Waukesha, MWM Deutz and Caterpillar requirements.
• Biogas — PWR BIOGAS 40, low ash with strong resistance to oxidation and nitration, formulated for the corrosive by-products of biogas combustion.

Do not use a diesel engine oil in a gas engine. Gas engines need controlled low ash: too much ash causes deposits on valve seats and poisons exhaust catalysts, and the damage accumulates quietly over thousands of hours.

Step two: 15W-40 or 20W-50?

PWR XTB 15W-40 is the default. It starts more easily on a cold winter night in Sulaymaniyah or Kirkuk, carries the broader approval list, and is available in a 20L pail as well as the 208L drum. Move to PWR XTB 20W-50 for high-hour engines whose clearances have opened up, and for continuous high-load running in extreme ambient temperatures where the operator wants a thicker film and lower oil consumption.

Step three: transformer and switchgear oil

The category also covers electrical insulating oils, which are a different product entirely:

• PWR ELECTRO — non-inhibited naphthenic oil with good dielectric properties, oxidation stability and heat transfer, and excellent low-temperature behaviour achieved without pour point depressants.
• PWR ELECTRO INH — inhibited, with antioxidant additives for much longer service life. Highly resistant to oxidation, prevents sludge and acid formation, free from corrosive sulphur.

For a transformer expected to stay in service for decades, the inhibited oil is normally the economic choice; the non-inhibited grade suits applications where the oil is changed or reconditioned on a defined cycle. Either way, insulating oil must be tested, not assumed — dielectric strength and moisture content decide when it needs attention.

Step four: service intervals on a machine that never stops

Count running hours, not calendar months. A set running twelve hours a day accumulates a truck's annual duty in a matter of weeks, so the hour meter is the only reliable service record. Start from the engine manufacturer's figure, commonly 250 hours, and let used-oil analysis decide any extension — reserve alkalinity, soot, viscosity and fuel dilution. On high-sulphur fuel, assume shorter rather than longer.

One practical point that costs operators more than oil choice does: generator air intakes in this climate ingest enormous quantities of dust. An air filter that has been cleaned by beating it against a wall is no longer an air filter, and the abrasive it lets through will wear the engine out regardless of what is in the sump.

Frequently asked questions

Not sure which product a vehicle, machine or fleet needs? Try the Cyclon oil selector, or send us the details and we will specify it in writing.