Do you have any port powered
converters?
Absolutely not. The serial port does not supply
enough current to drive enough units at high enough data rates
(baud rates) for us to bother with designing port powered
converters.
I have a power source that
exceeds the rated 15VDC input voltage of your converter, what can
I do?
One of two things. First if it is possible, use a
AC/DC transformer similar to our PS9. If this is not an
option you have the capability of extending the rated voltage of
the 485-25x or 422-25x to 60 Volts with the PWR-ADPTx.
Do you have a
RS485 to RS422 converter?
Not at
this time. However, you can accomplish this with two of our
units and a null modem connector. By attaching a 422-25A to
a DB25-NULL, DB25M-DB25M Gender Changer, and a 485-25E, you can
effectively converter RS-422 (4 wire) to RS-485 (2 wire).
Do you have 4-wire
RS485
converters?
No.
Do not mistake our 422-25x RS-422 interface converters for 4 wire
RS-485 converters. While a person may wire our RS-422
products in a multi-drop environment, they are designed for single
ended applications.
I have more than one
(non-addressable) RS-485 device, can I network them in a way that I
will only communicate with one of the devices at a time?
Yes.
With the 485-ADR you can network
non-addressable RS-232 or RS-485 devices on a single twisted pair!
Your converter works fine up
to a distance of "blank" feet, but after I extend the
run it stops working correctly, why?
This
could be caused by any number of problems, from EMI to RFI in you
field application, to open wires. Older or even non standard
RS485 devices may even cause this problem to occur. Refer
to the troubleshooting section of our application
notes to help isolate this problem.
What does the L mean (example
part # 485-25EL)?
L
designates extended temperature range and in all cases the
extended temperature range is -40° to 85º C (-40º to 185º F),
while the normal operating temperature for the non L version is
0º to 70º C (32º to 150º F).
My computer has a 9 pin
serial port, but your converters are DB25, can I still use them?
Absolutely.
All converters are shipped with a DB9F to DB25M adapter for
connection to PC's utilizing the 9 pin serial port. You can
review more information on the RS232 port on our specs
and application notes pages.
Can I hard wire DTR & RTS
to your optically isolated converter?
We do
not recommend it, but you can hard wire the +12VDC required for
DTR. However, as RTS is used to control data direction (flow
control), this can not be hard wired as it swings from +12 VDC to
-12VDC.
Why is termination so
important?
This is
a difficult question to answer here. To find more in depth
information on cabling and terminations go to the applications
notes.
