Technical Support Contact

Hardware & peripheral

How to resolve a fault that makes the ERR indicator on the Main Unit blinking or ON?
ERR indicator blinking:
Most of the ERR blinking is due to the new user program (incorrect syntax or instruction) or its user program in the PLC was lost, also that may occur with hardware breakdown or foreign object into the PLC. If the blinking happens, turn OFF and take it out to do the visual check then to review its user program. Let the PLC STOP then turn ON power, download new program and let PLC RUN. If the ERR still blinking, please change another PLC and download the same program, try again.
ERR indicator ON:
This PLC may be due to insufficient power input, too frequent interrupts, too many loops in the program, by extreme electromagnetic interference, irruptive of foreign objects circuit damage, etc. That cause PLC unable to start, WDT timeout or CPU unable to execute normally so the ERR turned ON. In this case, check its power input, then cut off power to move PLC away from the big current wires or high-intensity source of interference, also remove all communication wires. After that, let the PLC STOP and turn power ON. If the ERR still ON, please send this fault PLC back to original vendor. But, if the ERR is due to switch to RUN, the issue may be on the user program, application or the memory.

If the loader of the PLC's output is to drive an inductor (solenoid, contactor, relay, etc.), how to protect the output point when it is turned off?
  1. For a DC inductor, please parallel connecting a flyback diode with the inductor (opposite polarity).
  2. For a AC inductive, please parallel connecting a R/C spark killer with the inductor .

What is the common structure of digital input points in a PLC? What is the input difference between VH and VB series PLC? How to trigger the input point?
Generally PLC input point must have a photo-coupler to do isolation, then uses the clear signal at the inside of PLC to do logic processing.
So to trigger a digital input point of VB / VH uses DC 24V through its current limiting resistor and photo-coupler to make this point is interpreted as ON.
Whole digital inputs in the VB series (main unit, expansion unit or expansion module) are equipped with bidirectional photo-couplers. If want to trigger those input points by the negative logic (Sinking), please use the positive (+) of DC 24V connects to the S/S terminal (it is to one side of the photo-couplers), then current by an X input terminal through a switch (dry contact or NPN transistor) to the negative (-) that became a circuit. On the contrary, the positive logic (Sourcing) that S/S point is connected to the negative (-) of DC 24V, while positive (+) through a switch of dry contact or PNP transistor, and then trigger the X input.
However, the VH Series PLC is equipped with single directional photo-couplers only (Sinking). The positive of photo-couplers have connected with the DC 24V (+), and the COM terminal has connected with the DC 24V (-) in a VH main unit or an expansion unit. So just use the COM point through a dry contact or NPN transistor to trigger the X input.
Note: Please do not connect an exterior DC 24V's positive (+) at the COM terminal of the VH series main unit or expansion unit. But at the expansion unit of VH, you need to input a DC 24V (+) to the 24+ terminal for supplying the positive of internal photo-couplers, then use the DC 24V (-) through a switch to trigger an X point.

I have installed the VB-DB1R data bank expansion card in the VB series PLC, why using the DBWR / DBRD instruction or the Ladder Master could not access the data? Does it have some matters needing attention?
The VB-DB1R card uses Lithium batteries to keep huge data in the SRAM, when the PLC without power supply. If the batteries are low or shorted by conductive material to make its voltage dropped, the data will be disappeared also the RTC (Real Time Clock) will restart at 1/1/2000. Since its data format and identification code is in the SRAM, failed battery will cause the main unit unable to identify this card, then could not to access it.
The VB-DB1R card shall be kept in a room temperature and low humidity, prohibit encountered to any conductive material. To install or remove this card must turn OFF the power of PLC. Also, to remove a card from a PLC, use the hook of accessory is recommended. If the low battery flag M9005 has been turned ON, please use the Ladder Master to backup the data in the VB-DB1R immediately, then replace a new card and write the backup data into the card.

The PLC has been set a program password and lost the password, so could not to read its user program in the PLC. How can I remove the password in this PLC?
Since the VIGOR PLC has provided to input a password and the purpose is to protect intellectual property rights of the user program in this PLC. When the PLC is locked by a password, to read the program from this PLC must check its password otherwise PLC will not allow to upload its program. If the password is lost, the only way to remove the password is using the “Initialization” to erase all the user program, latched area, the setting of CP2 and the password become default values. Then this PLC needs to download a new user program for a new application.

There is an DI/DO expansion unit, expansion modules or special module at the right side of a PLC main unit, why the function is not properly?
Must turn OFF the power of whole the PLC system if want to add in or remove out any component in the system. Otherwise, “Hot-Swapping” without shotting power down that may cause the system damaged, then unable to do the correct process. Also, please check the inner power supplies for all the expanded system, is it exceeded or not? Or, are the expansions over the PLC's system allowed range?