© Agrowtek Inc. | www.agrowtek.com | Technology to Help You Grow™
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Introduction
GrowControl VX series digital interface modules connect Agrowtek’s intelligent controllers to devices in your
growing environment.
VX8i and VX12i modules feature eight discrete DC FET ouputs for directly driving 15Vdc/24Vac irrigation
valves and other Dc devices. VX12i models also features four analog inputs. Analog inputs allow the connec-
tion of SXL optical liquid sensors and other third party analog sensors for integration. FET outputs connect
to DC signaled devices such as relays/contactors, solenoid valves, and to PWM driven devices such as motor
speed controllers or lighting dimming inputs.
Inputs (VX12i only)
Four analog inputs are provided for connection of of various analog 5Vdc third-party sensors, or discrete
sensors. Inputs are rated 0-5Vdc (or 0-20mA if current jumper is installed for the channel) and are 12 bit
(4096 steps.) Inputs may be used for discrete or analog type sensors. A 5Vdc 500mA power supply is includ-
ed on board for powering analog sensors or providing a signaling voltage for discrete or dry-contact sen-
sors.
Typical Discrete Sensors
Typical Analog Sensors
SXL Optical Liquid Detection Sensors
Moisture
Float Switches
Pressure
Door/Window Switches
Temperature
Flow Switches
Other
Outputs
Eight heavy-duty transistor outputs with transient and flyback protection are designed to connect to DC
contactor and relay coils for electrical panel control. Each transistor output is rated at 1A pilot duty (2A max
total per unit) and will switch the supplied voltage out to the terminals. Heavy duty FET transistors offer
robustness and reliability with ultra low heating.
Pulse Width Modulation (PWM)
The first six (6) transistor outputs may be operated in a 1kHz square-wave PWM (pulse width modulation)
duty frquency between 10% and 90%. This allows integration with most lighting dimming controls and fan
speed controls.
Duty values below 10% will be output as 0%. Duty values above 90% will be output as 100%.
FREQUENCY
1kHz
0V
Vin
OFF ON
DUTY CYCLE % =
ON TIME
OFF TIME
x 100
