The ES-301 UE is a four digit, 100 minute master timer with six top-front mounted controls (UP, DOWN, STOP, MIN-SET, SEC-SET and RESET). Each of the controls are actuated by pressing the appropriate switch. The timer will run continuously unless stopped (except in the case of option "Z", where it will stop at 00:00). If stopped the timer will hold the time displayed when it was stopped. Pressing the UP switch will start the timer counting up from the time on the display; the DOWN switch will start the timer counting down from the time on the display. The STOP switch stops the timer count. The RESET switch functions as a combination reset/preset switch. The first time it is pressed, the display is reset to 00:00. If pressed again (within 5 seconds) the timer is set to the last manually preset time. The MIN-SET and SEC-SET switches advance the selected digit pair. In order to store a manually preset time in memory, either the UP button or the DOWN button must be pressed after setting the timer to the desired preset time. The timer may be reset or set while it is stopped or while it is running. If the RESET switch is pressed while the timer is running the timer will not count until the switch is released. When a SET switch is pressed while the timer is running, the timer will stop until either the UP or DOWN switch is pressed again. If option "R" is specified, the unit may be remotely controlled via the rear-mounted 9-pin connector (pin designations are given below). A momentary short to ground or a 5 volt logic "O" is required to actuate the desired function. A remote input should be held low for at least 25 milliseconds to insure that it will be recognized. The connector also provides access to the optional relay contacts (see option "Z" or "Y" on page 3).