85.2230—Steady state test dynamometer—EPA 91.
(a) Special calendar and model year applicability.
The requirements of § 85.2229 apply concurrently for tests conducted under Emission Performance Warranty on 1995 and earlier model year vehicles or engines until December 31, 1993, after which the requirements of this section are solely in effect. The following exceptions apply: In a state where the Administrator has approved a SIP revision providing for implementation of a basic centralized program meeting the requirements of part 51, subpart S of this chapter, according to the schedule specified in § 51.373 of this chapter, the requirements of § 85.2229 are concurrently in effect until June 30, 1994 for 1995 and earlier model year vehicles or engines; in a state where the Administrator has approved a SIP revision providing for implementation of an enhanced program meeting the requirements of part 51, subpart S of this chapter, according to the schedule specified in § 51.373 of this chapter, the requirements of § 85.2229 are concurrently in effect until December 31, 1995 for 1995 and earlier model year vehicles or engines.
(b)
The chassis dynamometer for steady state short tests must provide the capabilities described in paragraphs (b) (1) through (7) of this section.
(1) Power absorption.
The dynamometer must be capable of applying a load to the vehicle's driving tire surfaces at the horsepower and speed levels specified in paragraph (c) of this section.
(2) Short-term stability.
Power absorption at constant speed may not drift more than ±0.5 horsepower (hp) during any single test mode.
(3) Roll weight capacity.
The dynamometer must be capable of supporting a driving axle weight up to four thousand (4,000) pounds or greater.
(4) Between roll wheel lifts.
For dual-roll dynamometers, these must be controllable and capable of lifting a minimum of four thousand (4,000) pounds.
(6) Speed indications.
The dynamometer speed display must have a range of 0 mph to 60 mph (or 0 kph to 100 kph), and a resolution and accuracy of at least 1 mph (or 1 kph).
(7) Safety interlock.
A roll speed sensor and safety interlock circuit must be provided which prevents the application of the roll brakes and upward lift movement at any roll speed above 0.5 mph (0.8 kph).