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OPERATION:
The Agrónic Monocable system operates with a linking unit, the Agrónic Monocable Link (EAM), which con-
nects to the Agrónic using a RS485 bus or RS232 serial port and the ModBus communication protocol. The EAM
supplies the 24 Vdc which powers the entire Monocable system and distributes it through a 2-wire cable which in
turn connects all the Agrónic Monocable Modules (MAM).
Up to 120 MAMs can be connected to a single EAM (depending on the total length and type of cable used).
Each MAM is identified by a number and can be placed in any order along the line. This identification can be
changed at any time using the Modules Reader.
The MAMs are organized into groups of 10 (from 1 to 10, from 11 to 20, etc.). Every 6.6 seconds the output
status is sent to a group and each MAM in this group sends the status of their inputs, totals, sensors, etc. The
fewer groups on a line, the faster the communication is between each MAM. In the worst possible case, with 120
MAM connected on a line, it will take 80 seconds to connect to all the MAMs.
MAM with priority: if it is necessary that one MAM in particular needs to act very rapidly, either in the solenoid
activity or sending the sensor or digital input readings, it can be configured as an “MAM with priority”. This module
will connect to the EAM every 6.6 seconds. To do this the MAM occupies one communication space for each
group, which in turn means the MAMs that occupy its place in each group cannot connect to the line. Example: if
MAM 1 has priority, it cannot connect to the line, and nor can 11, 21, 31... or 111.
INPUTS AND OUTPUTS:
DIGITAL INPUTS:
There are up to 10 digital inputs, D1 to D10, which can function as a digital input. Inputs D3 to D10 can also
function as meters. When ameter is connected to adigital input, it has the ability to count up to 5pulses per second.
The common input return is connected to the terminal marked CD. The inputs corresponding with the termi-
nals run from D1 to D10.
The contacts on the unit that connect to a digital input must be free potential contacts.
SENSOR INPUT:
The MAM has one analog input for reading sensors that emit a 4 – 20 mA signal. The input also has a 200 Ω
resistor which can read voltages of 800 mV for the 4 mA and 4000 mV for the 20 mA.
The sensors are powered at 12 Vdc provided by the MAM. The sensor only receives power for the time that
has been configured, as for the rest of the time it has no power to it. The time between readings is configured on
site, and can differ according to the function of the MAM and the sensors. The sensor power is connected to the
0V and 12V terminals and the sensor reader to A1 terminal.
LATCH SOLENOIDS:
MAM can operate with two or three wires latch solenoids using:
-2-wire latch solenoids: the common return of all the solenoids is connected to CR terminal and the other
solenoid wire is connected to the terminals marked as R1 to R8.
-3-wire latch solenoids: With this type, the number of solenoids that can activate the MAM are cut in half.
The solenoid connections will be done at the common return borne at the CR terminal and the start and
stop wires at the following terminals:
solenoid 1 start at terminal R1 start at terminal R2
solenoid 2 start at terminal R3 start at terminal R4
solenoid 3 start at terminal R5 start at terminal R6
solenoid 4 start at terminal R7 start at terminal R8
The trigger voltage in the solenoid is programmable, and can be of 12 or 16 V.
Keep in mind that many latch solenoids with 3 wires can function perfectly well with 2 wires, if it were neces-
sary to use them.
