HomeTerexTerex T90

Terex T90 Generator Set

The Terex T90 is a 80 kW (100 kVA) diesel standby generator set powered by a Cummins/Onan QSB5-G2 NR3 engine. It is available at 208 V, 220 V, 240 V, 440 V and 480 V, 3-phase, 60 Hz and rated 300 A. The set measures 2790×1190×1620 mm (109.8×46.9×63.8 in), weighs about 2445 kg (5390 lb) and produces 66 dBA at 7 m.

80 kW
Standby
1
Document types

Specifications

Fueldiesel
Frequency60.0 Hz
Standby power80 kW
Standby kVA100
Prime power72 kW
AlternatorStamford/AvK UCI274DIL32D
Voltage options208 V, 220 V, 240 V, 440 V, 480 V
Phase3 phase,1 phase
Rated current300 A
Power factor0.8
Circuit breaker300 A
Dimensions (L×W×H)2790×1190×1620 mm
Dry weight2445 kg
Sound level66.0 dBA @ 7 m

Engine

Cummins/Onan QSB5-G2 NR3
Rated speed1800 rpm

Maintenance & consumables

for the Cummins/Onan QSB5-G2 NR3
ItemSpecCapacityPart #Interval
Air filter find
Fuel filter find
Oil filter find
Belt find
Coolant16.5 litres
Oil8.4 litres

Compatible filters for the Cummins/Onan QSB5-G2 NR3 — cross-referenced via Donaldson. Options to verify against your serial number, not confirmed for this exact unit.

  • Air filter: Donaldson P635903 Donaldson P635979

Common questions

What is the power rating of the Terex T90?

The Terex T90 is rated 80 kW standby (100.0 kVA).

What engine does the Terex T90 use?

The Terex T90 is powered by the Cummins/Onan QSB5-G2 NR3 engine.

What fuel does the Terex T90 use?

The Terex T90 runs on diesel.

What alternator does the Terex T90 use?

The Terex T90 uses a Stamford/AvK UCI274DIL32D alternator.

Troubleshooting

14

Symptoms & remedies

SymptomCauseRemedy
No generator output voltageCircuit breaker trippedReset circuit breaker
Low generator output voltageVoltage adjustment set too lowAdjust voltage potentiometer
Low engine speedCall TEREX Service
Fluctuating or surging generator output voltageCheck engine fuel, oil, and air filters
High generator output voltageVoltage adjustment potentiometer set too highAdjust potentiometer
High engine speedCall TEREX Service
Fluctuating generator output voltage stabilityLoad may be the causeRedistribute load if possible
Engine won't crankLoose battery cableCheck cables and battery electrolyte level. Recharge as necessary
Engine runs, but loses power under loadClogged fuel systemCheck fuel system
Engine shuts downOil Pressure Switch not opening automatically and TROUBLE LIGHT onImproper coolant use a 50/50 on
TROUBLE LIGHT on CONTROL PANEL is illuminatedBroken fan beltInspect fan belt and replace as needed
Voltage does not come up to the rated voltageInternal problem with the generator endCheck for even reading across the lines, if they are not this would mean you probably have a problem with the wiring of the switch or generator. If the generator voltage reads correctly, contact the TEREX service department.
Uneven reading between the legs when applying 24 volts to the field wiresRecheck your wiring connections. After you have the field wire connected start the unit again and check your output voltage. It may still be necessary to flash the fields to restore residual voltage.
Malfunction discoveredIdentify symptoms, troubleshoot, perform repair, return to service

Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.

Parts

10
Part #DescriptionQtySystem
101-4000Gasket385Gasket PartsGeek
127-0826Battery685Battery PartsGeek
153-5720Thermostat147Thermostat PartsGeek
250-0486Oil Filter34Oil filter PartsGeek
250-0488Spark Plug31Spark plug PartsGeek
8C-3600Coolant Filter375Coolant filter PartsGeek
8C-3601Air Filter250Air filter PartsGeek
8C-3620Belt350Belt PartsGeek
8C-3627Fuel Filter30Fuel filter PartsGeek
134277T70, T90 & T120 Super Quiet Generator Maintenance ScheduleService part / kit PartsGeek

Service, wear & replacement parts referenced for this model and its engine — confirm the exact part for your serial number. See the full parts catalog to search and cross-reference.

Fuel consumption

RatingLoadL/hgal/h
Prime4.416.6
Prime50%3.413.0
Prime75%5.019.0
Standby5.621.0
Standby100%6.023.0

Available documents

Service manual — 134277 (Terex)