Examples – PASCO CI-6462 Relay User Manual

Page 5

M o d e l N o . C I - 6 4 6 2

Ex a m p l e s

be compared with that range. If min

≤ x ≤max, then the function equals 1. If x < min

or x

> max, then the function equals 0.

and(a, b)

This function equals 0 if either of the arguments equals 0; otherwise the

function equals 1.

or(a, b)

This function equals 0 if both of the arguments equal 0; otherwise the

function equals 1.

not(x)

This function equals 1 if the argument equals 0; otherwise the function

equals 1.

Examples

The input that controls the relay can be any measurement or combination of multiple
measurements from any sensor. Below are some examples.

Temperature Control

Temperature control may be desirable on a variety of apparatus such as an incubator
(made with a low-power light bulb and a box), a small greenhouse equipped with a
cooling fan, or a thermal cavity (such as PASCO part TD-8580A).

You can control the temperature by having the Relay turn on a fan when the apparatus
is too hot, or by turning on a heater when it is too cold. The example from page 2 or 3,

outputstate(1, 1, T>30)

could be used for either purpose, depending on whether there were a fan circuit con-
nected to the Normal jack or a heater circuit connected to the Activated jack.

You can also use the Relay to control a bell or light to indicate when the temperature
is within an acceptable range (or not) with a definition such as:

outputstate(1, 1, inrange(20, 30, T))

This would activate the Relay when the temperature is between 20 °C and 30 °C.

Fan Cart on Inclined Track

In this example, a fan cart starts pushing itself up an inclined track whenever it gets
close to the bottom.

Setup a fan-equipped cart on an inclined track with a motion sensor (part PS-2103) at
the lower end. Connect the Relay so that the fan turns on when the Relay is activated.*
Enter this equation in the Calculator:

outputstate(1, 1, and(x>0.25,

<0))

Define x as position and

as velocity.

Start data collection and release the cart about 25 cm from the motion sensor (oriented
so that the fan will push the cart up the incline). The fan is on when the cart is closer
than 25 cm and rolling toward the sensor; otherwise it is off.

Change the incline of the track, or change the distance at which the fan turns on and
observe the results.

3.5 mm (

inch)

mono phone plug

4 mm banana

plugs

to Relay

to fan

accessory

*The PASCO Fan Acces-
sory (part ME-9491) can
be controlled by the
Relay via the cable pic-
tured below, which you
can make with commonly
available parts.