What is the difference between on delay timer and off delay timer?

What is the difference between on delay timer and off delay timer?

After the input is turned on there is a delay before the output is turned on. After the input is turned off there is a delay before the output is turned off.

How do you use delay timer as OFF delay timer?


  1. Rung 0000 :- Latching is done using output coil to stay ON even Input is turned off.
  2. Rung 0001 :- since the Start Input is used as normally closed input, Output Coil is attached as interlocking, so that it won’t turn on timer at the beginning of the program.
  3. Rung 0003 :-

What is off delay timer definition?

With OFF-delay operation, the output turns ON at the same time as the input and then the output turns OFF when the Timer contacts switch after the set time has expired. The set. time is calculated from when the input turns OFF.

Where are off delay timers used?

Off-delay timers can be used in air-conditioning systems to hold the blower motor in operation for a specific time period after the thermostat has turned the cooling compressor off. They may also be used to operate electrical devices and motors for a specified time, such as coin-operated dryers in commercial laundries.

What is the basic difference between TOF and TON timer?

A TON is a timer on delay and a TOF is a timer off delay. Both have EN bit, DN bit,TT bit. They both time to a preset. The differents between the two is TON times to on and the TOF times to off.

What is delay relay?

The purpose of time-delay relays is to start or stop currents from moving in coils and armatures, the moving parts of electrical mechanisms. They are designed to allow electrical circuits to release at certain times. These types of relays are triggered either by the opening and closing of a signal or by input currents.

What is retentive on delay timer?

Retentive ON delay timer is to delaying the ON time, if input goes off in between, it will resumes the accumulator value and input turns ON, it will start running for the resumed value.

How does a Dashpot timer work?

The dashpot timer functions when a magnetic field forces a piston to move within a cylinder when the coil is energized. The movement of the piston is limited by fluid passing through an orifice on the piston. The amount of fluid passing through the orifice is controlled by a throttle value, which determines the delay.

What is the function of time delay valve?

Time delay valve is a combination valve used to set the operation time as per the requirement. The time delay can be increased or decreased by adjusting the flow through the non-return flow control valve. The change invariably increases or decreases the time taken to fill and pilot actuates the direction control valve.

What is off time delay relay?

Also called normally-open, on-delay relays. 2: Normally-open, timed-open. Abbreviated “NOTO”, these relays close immediately upon coil energization and open after the coil has been de-energized for the time duration period. Also called normally-open, off delay relays.

How does a TOF timer work?

The TOF instruction begins to count timebase intervals when the rung makes a TRUE-to-FALSE transition. As long as rung conditions remain FALSE, the timer increments its accumulated value (ACC) each scan until it reaches the preset value (PRE).

How do you calculate TOF and tons?

Turnover number (TON) = number of moles of reactant consumed/(mole of catalyst). Turnover frequency (TOF) = TON/time of reaction.

What is an off delay timing relay?

True OFF Delay Relay. An ICS true off delay relay is an off delay relay that provides a relay contact for a preset delay period after voltage is removed from input terminals A and B. When the input voltage is removed, the off countdown timer begins. At the completion of the delay cycle, the relay is de-energized and the contact transfer is made.

What is time off delay?

The term “on delay” indicates that a preset time must pass after the timer receives a signal to turn on before the timer’s contacts change state. The term “off delay” indicates that a preset time must pass after the timer receives a signal to turn off before the timer’s contacts change state.

How do time delay relay work?

A time delay relay is a relay that stays on for a certain amount of time once activated. This time delay relay is made up of a simple adjustable timer circuit which controls the actual relay. The time is adjustable from 0 to about 20 seconds with the parts specified.

What is time delay switch?

A time delay switch or TDS is a switch which is linked to a timer, allowing the user to delay on/off cycles of the switch.