LC4 Light Controller
The LC4 Light Controller
allows the DAMSystem3
software to directly schedulethe on/oﬀ timing of up to 4
independent external devices.
By bypassing the simple
internal timers that many
incubators have, the Light
Controller hardware andDAMSystem software
combination makes available awide array of light pulse
patterns for both entrainmentand stimulus/response
purposes.
External devices such as theTroemner multi-tube vortexer
may also be controlled togenerate shake-pulse
sequences for sleep deprivation.

LC4Specifications

Each of the 4 output channels is switched
on/oﬀ by a solid state relay within the LC4enclosure. The relays are rated for up to240VAC, 50/60 hz operation at 3 amperes,and each is fuse protected against overload.

• Power per outlet: 3A, 240VAC 50/60 hz• AC power outlet (4): NEMA 5-15 (USA)• AC Power Input: IEC60320 C13• Dimensions: 6.8” x 4.8” x 4.2” LWH

An input AC line cord provides power to therelays, and output cords provide switchedpower from the relays to the lights or devices
to be switched. The connectors for AC input
and output are the North American
standards: IEC60320 C13 for input andNEMA 5-15 for output.

• Enclosure material: Aluminum• Interconnect: 4 wire, 6 position, RJ-11
modular telephone line jack to DAMSystem
network for 9V DC power and datatransmission

The unit is housed in a robust aluminum
enclosure.

• Operating environment: normal
laboratory, non-condensing

Features• Programmable on/oﬀ switching of 4 ACoutlets• Pulse duration from 0.1 second to 99
hours• Single, periodic, or random pulse
repetition• Incubator lighting control• Troemner multi-tube vortexer pulsing forsleep deprivation

TRIKINETICS
TriKinetics Inc USA

1/5

LC4 2018.11

Checkout
1. Launch the DAMSystem3 program and select Light Control in the Display Selector.
2. Click the upper-left box in the checkbox matrix to connect pulse 1 to output channel 1.
3. Connect the LC4 Light Controller to the DAMSystem network with a phone cable andselect Current Data in the display selector. Verify that the light status box in the upper rightof the DAMSystem window turns orange (on) or blue (oﬀ).
4. Connect an AC cord to the input power receptacle and a standard table lamp plug to oneof the output receptacles. Adjust the settings in the Light Control panel to make thechannel go on (at the next reading) and verify that the lamp does indeed come on.
5. Plug the incubator light or device cords into the output receptacles in place of the test
lamp and adjust the settings to control the lights or devices as desired.

Light Controller Settings

ExamplesChannels 1 and 2

24-hour light/dark cycle: On at 8:00 AM, Oﬀ at 8:00 PM

Channel 3

Randomized 2-second pulse every 10 seconds ONLY during the period
between 02:00:00 and 06:00:00 every day. Note the use of 2 pulses
combined with AND logic (output is on when both pulses are on.)Channel 44-hour pulse at midnight followed by 1-second pulse at 6am. 2 pulses
are combined by OR logic to control output channel 4 (the output will beon when either pulse is on.) No repeats will occur.

TriKinetics Inc USA

2/5LC4 2018.11

Light Channel Matrix
The software generates 8 independent pulses, each of which may be assigned to one or moreof the 4 physical output channels according to the matrix of check boxes. An output channel
with a single assigned pulse will be On when the pulse is On, and Oﬀ when the pulse is Oﬀ.
When multiple pulses are assigned to a single channel, the logic to combine them will be
determined by the +/x symbol displayed below the pulse column. ‘+’ (or logic) will cause thelight channel to be on when any of its assigned pulses is on, and ‘x’ (and logic) will turn on theoutput only when all of the assigned pulses are on.
When an output channel is configured to be On, its corresponding outlet on the LC4 Light
Controller will be energized with AC power.

Pulse Algorithm
Each pulse is individually controlled by 3 parameters: On Time, Duration, and Repeat Period.
A pulse will be turned On when the Day of its On Time parameter is today (0), and the H:M:S of
its On Time equals the H:M:S of the computer clock.
The pulse will then stay On for the H:M:S of its Duration parameter, after which it will go Oﬀ.
As it does so, the Repeat Period parameter will be added to the On Time to form the new On
Time for the next pulse. This On/Oﬀ cycle will continue at the Repeat Period for as long as theprogram is operating.
Several special cases are of interest. If the Duration is 0, the pulse will never turn On. If theDuration equals the Repeat Period, the pulse will never turn Oﬀ. If the Repeat Period is 0, onlya single pulse will be output, and it will not be repeated.

Changing the Settings
To change a time setting, place the mouse pointer over the number to be modified, and holddown the (left) button. If the tip of the pointer is above the centerline, the number willincrement, and if below, it will decrement. Note that some settings are restricted to multiples ofthe Reading Interval.

On TimeThe On Time for each light pulse indicates the time of day at which the pulse either was, orwill be, turned On. The digit in front of the hour indicates the day of turn-on, with '0' for today,'-1' for yesterday, and '+1' for tomorrow. As light pulses are turned on only at the Reading
Interval, the On Time is restricted to multiples of this interval.

Duration
The Duration sets the length of time for which the pulse is to remain On after turn-on. Thevalue may range from 00:00:00.0 (never On) to that of the Repeat Period (always On). If theDuration is set above the Repeat Period, it will be set to the Repeat Period when the settings
are saved. The timing resolution is 0.1 second.

Repeat Period
The Repeat Period sets the rate of pulse cycling, and with the Duration, controls the duty
cycle or 'On fraction' of the pulse. The pulse will be On for (Duration/Repeat Period) fraction ofthe time. If the Repeat Period is set to 0, only a single pulse will be output, and it will not berepeated. The maximum setting is 99 hours, or just over 4 days at 24 hours each.

TriKinetics Inc USA

3/5LC4 2018.11

Random Repeat Period
The Repeat Period may be randomized to vary the stimulation from pulse to pulse. To activate
this function for any pulse, click in the space to the right of the Repeat Period, toggling through3 options: Rn(randomize normal), Ru(randomize uniform), and blank(no randomness).
Operation is as follows:
For any pulse with its flag set to Rn, the Repeat Period becomes a normally-distributed
random variable, with a mean equal to the nominal (displayed) value, and a standard deviation
equal to the Sigma fraction of the nominal Oﬀ Time (Repeat Period - Duration). All Repeat
Period values will be within the range of Repeat Period +/- Oﬀ Time. The Sigma parameter will
adjust the width of the distribution, with 1% providing little variation in the Repeat Period, and100% providing wide variation over the allowed range.
For any pulse with its flag set to Ru, the Repeat Period becomes a uniformly-distributedrandom variable, with a mean equal to the nominal (displayed) value, and a maximum deviation
equal to Sigma times the nominal Oﬀ Time. Thus, in this case Sigma does not represent a true
standard deviation, but instead defines the absolute limits of the uniform variation about thenominal value as a fraction of the nominal Oﬀ Time.
In all cases, an immediate repeat may be generated, but only at the conclusion of a pulse,
and thus no partial pulse repeats will occur. Note that as long as the pulse duration is at leastas great as the reading interval, the MonitorLC or DayLight file will contain a record of the pulsetimes. Note also that the pulses may only be initiated at the beginning of a bin, so the Repeat
Period must be substantially greater than the Reading Interval for the randomizer to beeﬀective.

Hints
A single pulse (of the 8) may be used to control multiple light channels if all are to cycle On/
Oﬀ simultaneously. Simply check the boxes for these channels in the row of the pulse, and all
will be controlled.
A finite string of pulses may be generated by combining several of the 8 pulses, each ofwhich is set to produce a single pulse. Thus Pulse 1 could generate a single pulse today (0H:M:S), Pulse 2 could generate a single pulse tomorrow (+1 H:M:S), and so on, up to 8 pulses.
A single long pulse may enable or gate a series of short pulses by using the ‘x’ (and) logic
symbol. Thus a 1-hour sequence of short 1-minute pulses would be generated by “x”
combining on a single channel the 1-hour pulse with a repeating 1-minute pulse. The channel
output will only be On when both pulses are On. (If, however, the ‘+’ (or) symbol is usedinstead, the channel will be On whenever either pulse is On, negating any eﬀect of the 1-minutepulse.)

Notes
Light pulses are initiated only at bin boundaries, though they may terminate at any time
according to the Duration setting. The light status boxes are updated as each bin begins, justprior to any command changes to the lights. Thus the status box and status record in the LC
file reflect the state of the lights in the bin just ended (aligning itself with the data collected,
which similarly reflects activity in the bin just ended.)
The light status boxes reflect the On/Oﬀ state of the lights as commanded by the softwareand reported back by the controller. If a fuse is blown or a cable unplugged, the status willclearly be incorrect, and only a direct measurement of the light level itself will tell the real story.
(See DEnM Drosophila Environment Monitor or DAM2 Ambient Light Sensor.

TriKinetics Inc USA

4/5

LC4 2018.11

Vortexer Control
The LC4 is often used to power a vortexer shaking apparatus for sleep deprivation. Thisrequires short (2 second) pulses repeated often (every 10 seconds), the settings for which are
shown above in example channel 3. Because pulses can only be initiated at the Reading
Interval, it is usually best to operate the LC4 in this application on a separate PSIU9 andDAMSystem3 application with no activity monitors attached so that very short (2-second)Reading Intervals can be used. This is necessary for randomization of pulses at a 10-second
Repeat Period.

Incubator Light Wiring
To use these controls for incubator lighting, the lights must be disconnected from the internal
incubator timers and connected instead to conventional line cords with plugs suitable forconnecting to wall power. Make sure that the ballast transformers for the lights are included in
the circuit with the line cords - test each cord by plugging it into a wall outlet. If the lights work
properly in this case, the cord may be plugged into the LC4 for DAMSystem control.
NOTE: electrical connections to the incubator lights must be made by trained electricians
only.

Fuses
Fuses are provided in each of the relays to protect against overload. In the event of fuse
replacement, the exact same size and rating must be used (Littlefuse 217005.)

Ghost Flashes
The LC4 solid-state relays can output a microamp-level current, even when oﬀ, which
normally is of no consequence. But some compact fluorescent and led lamps can integrate thisminuscule ‘oﬀ’ current over a period of seconds or minutes into enough voltage to periodicallypower the lamp on for a brief flash of light. (This will not occur with normal fluorescent orincandescent bulbs.)
To prevent this, place a small incandescent bulb, like a 3-watt refrigerator lamp, on theoutside of the incubator and in parallel with the interior light which flashes. The load of theincandescent bulb when oﬀ will drain the microamp leakage current and prevent the flashing.

TriKinetics Inc USA

5/5

LC4 2018.11