Timer and counter
PT35 Seametrics Inc.

The PT35 digital counter-timer is designed to be used with Seametrics (or similar) meters and flow sensors that produce a pulse signal. It is typically used in water treatment and chemical dosing applications, most often in cooling towers and boilers. The PT35 serves as either a single or a dual timer, depending on whether one or both of its independent accumulators and timers are used.

When the PT35 is used as a single timer, the accumulator counts the pulses coming from the meter. When a pre-set number of pulses has been reached, output power turns on for a set time, and then the cycle repeats.

For applications requiring dual timers (typically, one chemical feed and one water bleed), both accumulators and timers are set to operate independently, even though input is from a single meter or flow sensor. A sequential function can be selected to lock one timer out while the other is operating. This prevents feed and bleed from occurring simultaneously.

The PT35 can be used with dry contact meters, contacting-head meters with solid-state pickups (Seametrics MJE meters), or insertion flow sensors (Seametrics IP, TX, and EX series).