Frequently Ask Questions

Q1)  What is the voltage required for this system?
A1)  This system works on 24VDC and requires 500mA current. If you have PLC Panel from which you can provide power supply or we can provide SMPS suitable for 110 / 230 Vac as per your requirement.

Q2)  What is the minimum voltage required for the system to works?
A2)  At least 16 to18 Vdc required at last switch of conveyor.

Q3)  How many Master Unit require for one conveyor and how many switches it can accommodate?
A3)  Per conveyor one Master unit is required as it can provide only one trip command. Normally maximum 60 switches in series can be connected to one Master Unit.

Q4)  If conveyor has more than 60 switches?
A4)  Another version of Master Unit and Sensor Module is available which can connect up to 200 switches in series or parallel.

Q5)  What is the distance required between Control Room (Master Unit) and first Pull cord switch?
A5)  Theoretically there is no limit for this but it can be up to 2/3 KM.

Q6)  Is any extra cabling required to be done on site?
A6)  No. Your existing 2 core control cable is used by this system. Only little modification required in control room to accommodate Master Unit at operator level.

Q7)  How Sensor Modules installed in field?
A7)  following figure1 shows Standard Pull Cord Switches connected in series

Above figure shows sensor module inserted inside Pull Cord Switch and little modification in control room cabling to accommodate master cum display unit. Sensor module has three wires, 2 wire (black and green) connected across 'NC' contact of PCS and red wire connected to common/return wire in PCS loop Now 2 core cable from field connected to Master cum Display Unit. Master Unit is powered by 24Vdc from PLC/Relay Logic Panel. Master cum Display Unit will provide Trip Contact to PLC/Relay Logic Panel.

Q8)  How Master Unit can recognize operated switch?
A8)  Master sends modulated frequency pluses over ridded on DC supply. Sensor module receives these pulses and modifies accordingly status of contact across it and sends back to Master Unit through Return (Common wire for all switches).Master analyzes it and display accordingly.

Q9)  What happens if more than one Pull cord operated from field?
A9)  Master Unit is capable to display more than one operated switches from field in cyclic manner.