wiegand data interference

I am having issues with a card reader in my elevator not sending wiegand data to my controller. all voltages are good at the reader. think it may be interference causing problems. will a wiegand extender fix this issue?

Reply to
Dave White
Loading thread data ...

It's impossible to answer that question without further troubleshooting.

Have you used a program like Hyper-terminal to check the data string at the controller end?

Reply to
Effenpig1

Have you tried pull-up resistors at the panel end on the data lines

0 and 1 yet?
Reply to
Silicon Sam

  1. What is the total distance of wire from reader to controller?
  2. Is the wire shielded with the shield connected to the ground lug at the central controller?
  3. Did you use the correct gage wire?

  1. Did that reader work reliably before?

Reply to
Bob La Londe

I used to work for an access control manufacturer and a wiegand extender was always recommended when interference was present. Another option that I've seen work well in the field is a unit now made by Schlage (or IR or whatever):

formatting link
These are expensive, though.

Reply to
kjwkjw

Use shielded wire, which is metal foil wrapped around the outside of the cable. This keeps outside electrical noise out. Ground one end of the metal foil.

Then there is "voltage drop" with long distances. Use a larger gauge wire for long distances. Something which starts out as 5 volts on one end can be

2 volts at the other end!

Voltage drop calculator...

formatting link
Shielded cable...
formatting link

Reply to
Bill

Does the reader travel with lift or is it at a floor for access? A lot of interferecne has been known to be in the traveler cables of some MFRs elevator. An extender may or may not work, that would depend on the tolerance of the receiver of the weigand signal.

Reply to
techie

Have you tried pull-up resistors at the panel end on the data lines

0 and 1 yet? nope, what value of resistor? is it manufacturer specific?
Reply to
Dave White

formatting link

Reply to
Dave White

the reader is in the elevator car. the problem i am having is finding an extender that will work with 18/2 wire with overall shield. all the manufacturers extenders that i can find spec out twisted pair wire, I think most of them convert the wiegand to 485 then back to wiegand at receiving end.

Reply to
Dave White

what settings would i set up hyper-terminal for? I would assume that is dependant on the wiegand format? I am using paradox R885 readers with 26 bit weigand format.

It's impossible to answer that question without further troubleshooting.

Have you used a program like Hyper-terminal to check the data string at the controller end?

Reply to
Dave White

I was just going by one install I did where 12 of the 36 readers would not read a card correctly and they all happened to be the readers that were farthest away. Our tech guru at our office said to put some pull up resistors between the power and Data 0 and power and Data 1 lines at the panel. Every reader was working after that.

I just happen to be going by the site tomorrow morning for remodel work, I'll look at the resistor value. It's been 3 years since I did it. It is a Lenel system with the Indala readers.

Gonna say it's either 1K or 4.7K resistors. I'll look when I get there and post tomorrow.

Reply to
Silicon Sam

What kind of system is it? Controller model? Brand and model of reader?

Reply to
Silicon Sam

I was just going by one install I did where 12 of the 36 readers would not read a card correctly and they all happened to be the readers that were farthest away. Our tech guru at our office said to put some pull up resistors between the power and Data 0 and power and Data 1 lines at the panel. Every reader was working after that.

I just happen to be going by the site tomorrow morning for remodel work, I'll look at the resistor value. It's been 3 years since I did it. It is a Lenel system with the Indala readers.

Gonna say it's either 1K or 4.7K resistors. I'll look when I get there and post tomorrow.

Reply to
Silicon Sam

I was just going by one install I did where 12 of the 36 readers would not read a card correctly and they all happened to be the readers that were farthest away. Our tech guru at our office said to put some pull up resistors between the power and Data 0 and power and Data 1 lines at the panel. Every reader was working after that.

I just happen to be going by the site tomorrow morning for remodel work, I'll look at the resistor value. It's been 3 years since I did it. It is a Lenel system with the Indala readers.

Gonna say it's either 1K or 4.7K resistors. I'll look when I get there and post tomorrow.

cool, I am going to my site today, will try out some different resistor values

Reply to
Dave White

.

Went by today, it was 4.7K resistors.

Reply to
Silicon Sam

What kind of system is it? Controller model? Brand and model of reader?

corrected the problem today. I split up the wiegand wires onto different pairs. works great now!

Reply to
Dave White

Usually set the baud rate at 9600 and leave the rest of the settings default.Hyper terminal is great for determining that the data is being sent properly before you start chasing ghosts. Kinda makes you regret tossing those old windows 95 laptops with the serial port among other reasons

Reply to
Effenpig1

Cabling-Design.com Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.