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• 2 or 4 independent 20 Amp SPST relays

Soundly constructed with a steel chassis and a case of durable, high-impact plastic

Dependable LED, 24-key audible keyboard, and programming capability

• Available with 20 or 40 programs, with or without the 8 input option

Remote accessibility via modem or Internet


   Because of their compact size and portability, the XT Table Top Timers are especially productive in scientific laboratories and other environments where quick and easy access to the keyboard and outputs is desirable.     

ChronTrol Table Top timers give you pushbutton control of up to four independent circuits which can be used to operate electrical devices such as lights, valves, solenoids, pumps, motors, fans or other equipment.

    With 20 independent On/Off programs - or up to 40 programs optional - you can exercise control right to the second, am and pm, every day of the week. Time settings are entered from the keyboard, with settings displayed on the digital clock during entry.

    Any or all of the available programs can be applied to an individual output, so the On/Off sequencing can be as simple or as complex as you require.

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Twenty programs (optionally 40)
2 or 4 independent circuits, 20 amp SPST relays
Up to 8 inputs for external activation
Cycle times from 2 seconds to 1 year
Separate On and Off time settings and Cycle times on each
6-digit display shows hours, minutes, and seconds
Directly replaces multiple mechanical timers

Tamper-resistant locking keyboard
Program up to one year in advance
Weekly cycle with day omission
9-volt battery backup keeps time 14 days during power outage
Battery backup keeps time even during power outages
12- or 24-hour time readout with Countdown timer
Easy to set and operate
Serial interface for remote monitoring

20 On/Off Programs (40 optional)
     Assign up to 20 independent programs, each with independent On and Off times, in any combination to the (up to four) individual circuits. Settings are made to the second from the keyboard, with AM/PM selection. Each program has individual cycle length and day-of-the-week omission settings.

Cycle Length
     Any program can be set to repeat, or Cycle, anywhere from once every 2 seconds (1 second on, 1 second off) to once a year. This feature can be used to simulate photoperiodic variation (to adjust for daily changes in the times of sunrise and sunset) and for short interval repetitive operations.

Day Omission
     Programmed operations can be selectively omitted on any day or days of the week, including holidays.

Calendar Operations
     ChronTrol's versatile calendar compensates for leap years and can be programmed for any number of holidays. On/Off programs may be set for specific dates.

Daylight Saving Time
     ChronTrol's real-time clock moves forward or backward one hour at Daylight Saving Time, automatically.

Countdown Timer
     ChronTrol's display can be set to show, in hours, minutes and seconds, the time remaining until the occurrence of any of its programmed events.

Easy Verification
Audible Keyboard Entry Entries made through the front panel keyboard are acknowledged with an audible tone for each key.
Next Program Program numbers can be assigned in any order, or ChronTrol will choose the next available program automatically.
Cross-Review feature allows the user to find out immediately what program or programs control any given circuit.

Manual Override
    Any circuit can be switched On or Off immediately without waiting for or disturbing programmed operations.

Power Fail Protection
     The time of day continues to operate, with crystal accuracy, during power failure. A nine-volt battery keeps the clock operating and protects the system memory to prevent the loss of stored programs. When power returns, all occurrences of On and Off events are accounted for, and outputs are switched to the proper positions for the current time, in sequence or all at once.

    Timers equipped with inputs can perform timing sequences that are synchronized or triggered by contact closures, and they can switch circuits On and Off based on external conditions. As many as 8 inputs can be wired to detectors, pushbuttons, or automatic equipment through a convenient rear panel connector.

Use as an Interval Timer
     Set up to 40 independent timing operations at once. Durations are set in hours, minutes and, if desired, seconds, from one second through one year. Timing intervals can be triggered and re-triggered through the keyboard, or by any of the 8 available inputs, or by other operational programs. Timing intervals can be set to repeat at any rate from two seconds (one second on, one second off) to one year.

Serial Communications
     All programming information and procedures can be accessed and performed via computer terminal through ChronTrol's RS-232 serial communication port. Or, by attaching a modem to this port, programming can by performed remotely over the telephone to facilitate centralized control.

Number of available circuits
     2 or 4 independent circuits.

Number of On/Off Programs
     20, or optionally 40, each assignable to any or all outputs. Each On/Off program includes the setting of:

ON time
(AM or PM, to the second)
OFF time
(AM or PM, to the second) (ON and OFF times can be set to occur on a specific date within the next 12 months)
Cycle length
(from 2 seconds to one year)
Day Omission
(inhibits program operations on any day or combination of days within the week, including holidays)

Optional interval timing
     Each On/Off program can be made an interval timer by specifying a duration of time instead of specifying an On or Off time. Durations can be set from one second through one year.

     .56'' continuous LED display of time-of-day or program information.

Power switching capabilities
0 to 277 volts AC
20 amps per circuit, 500W fluorescent, 2HP @ 240 VAC
20 amps per circuit, 1000W fluorescent, 1HP @ 120 VAC
• 6 amps tungsten per circuit @ 120 VAC
6 amps per circuit @ 277 VAC

     20 amp single pole, single throw

Circuit Status Indicators
     LED circuit ON indicator (one per circuit)

Number of available inputs: 8 digital inputs
Input timing: Edge triggered, with programmed enable/disable on each input
Minimum input pulse width: 100 ms (1/10 sec.)
Maximum input pulse width: Indefinite
Minimum delay between pulses: 2 seconds
Input electrical:
Current: 500 µA (requires switch closure or open collector individually or in groups)
Connection: 9-pin D-subminiature, female

Time base
     50/60 Hz line frequency (automatically selected) with crystal backup system.

Power source
120 volts AC ± 5%
    240 volts AC ± 5%

Power Consumption
     5 watts (not including relays)

Battery backup system
    9-volt alkaline battery provides 14-day protection of memory and time-of-day.

Serial Communications
Protocol: Serial asynchronous
Baud rate: 2400 baud
Data bits: 8 data bits
Stop bits: 1 stop bit
Parity: No parity
Signal level: EAI RS-232C (±12V)
Connection: 6-position, 4-conductor modular jack (RJ-11 type)

     High impact plastic (non-weatherproof)

     24-key, dome switch, audible.

Environmental Range
     0°F to 130°F / -17°C to 54°C; 0 to 90% relative humidity (non-condensing)

     4.75" x 8.25" x 5.00" (H/W/D) 120mm x 209mm x 127mm

Shipping Weight
     4 lb. / 2 kg.

     Limited, 1 year parts and labor.


Design and specifications subject to change without notice.

option code description
F Increase to 40 Programs
N8 Add 8 Inputs
240V 240VAC Power Source
B Add Interval Button
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