STYLITIS-10 INSTALLATION GUIDE [0516]
41
19.
SMALL RELAY DRIVING BY A DIGITAL OUTPUT
CONNECTION:
Any Stylitis-10 channel can be set as a digital output, which may be activated (become low, ie
channel and ground are short-circuited) either manually or when certain conditions
concerning other channels are satisfied. In the diagram below, the digital output is channel 8
and it is deactivated (marked as OFF).
When the conditions are satisfied, the switch closes, and current flows through the relay’s coil
inductor. However, the relay must be small, ie its coil must be activated via a current lower
than 20mA (the max cu
rrent the logger’s digital output can supply).
Such a relay can receive at its output (at the NC/ NO contacts) a direct (DC) voltage of 24V at
2A or an alternating voltage of 110V at 1A. Besides the voltage limit, there is a power limit as
well, ie, for instance, for a 12VDC load, a 4ADC current can pass through the contacts.
If the voltage and current through this small relay’s contacts do not suffice for your load, you
may use an additional relay (see the diagram below), which will use the first relay’s contacts
as an activation switch. Therefore, eg, with a 12V DC power supply, its coil must be activated
with 4A max current, while the tolerance of the output contacts concerning voltage and
current depend on your requirements (eg 220VAC/ 10A AC)
