Powerware ST-2400S user manual Operation

Power Supply:

The Model 2400S horsepower computer is normally operated from 110 to 125 VAC (60 Hz) using the outlet mounted power supply that is supplied with the unit. The power consumption of the computer is very low and the unit has a very high tolerance for power supply variations, so nearly any standard 115 VAC utility power outlet should power the unit adequately. See (below) information on a special (optional) “wide-range” power supply which will power the unit properly when the line voltage is either very low or very high.

The computer may also be operated from a source of 12 to 18 Volts DC such as a small DC power supply or 12 Volt storage battery. If a storage battery is used, be sure that it is properly charged. If the battery voltage is low, the POWER LED of the unit will flash “on” and “off” about once every second – indicating that the power supply voltage is inadequate to power the unit properly. NOTE: WHEN

OPERATING THE UNIT FROM A BATTERY OR POWER SUPPLY, THE POLARITY (+/- WIRING) MUST BE CORRECT OR THE UNIT WILL NOT OPERATE. WIRING A BATTERY OR POWER SUPPLY TO THE UNIT WITH IMPROPER POLARITY MAY RESULT IN DAMAGE TO THE UNIT.

Operation of the unit from a 110 to 250 VAC 50 to 60 Hz power source

A special “universal input” power supply is available (as an option) which will allow the unit to be operated from a wide range of AC power sources – both domestic and international.

This power supply has a detachable power cable which may be easily replaced with a power cable which matches the local power system.

This power supply is also very useful when operating the unit from power sources which may be lower than standard and/or slightly erratic. This power supply will result in proper operation when the AC power source is a low as about 90 Volts AC.

Operation:

The horsepower computer normally operates with a two second measurement cycle. It can optionally be factory programmed for a one second measurement cycle. During the measurement cycle, the RPM of the dynamometer shaft is measured along with the torque sensed by the dynamometer load cell. At the end of each measurement cycle, the RPM and TORQUE values (averaged over the measurement interval) are displayed and the POWER and % TORQUE RISE

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