Answer / binu

RS232 is for a shorter distance i.e around 45 ft.
RS485 is for longer distance. Can work fine for around
1.5Kms

Answer / deep

RS 232--PPI(point to point interface/2 nodes)
RS 485--MPI(maximum point interface/32nodes)

Answer / binu

Mr.Gyani,

There is no protocol changer for RS232/485. RS 485 is used
for longer distances, higher speeds and more noise immunity
than RS232. RS485 will also support 32 other statio i nthe
same line.
RS485 can be used for distance up to 1.5KMS without any
effetc in speed whereas RS232 is used only up to 45 ft.

Answer / ankush agrawal

RS 232--PPI(point to point interface/2 nodes)
RS 485--MPI(maximum point interface/32nodes or more)
RS 422--MPI(MAXIMUM POINT INTERFACE/10NODES)
ADVATAGE OF RS485 over RS232

high distance (4000 Feet)
high noise immunity
No of nodes is high

there is no difference in terms of speed in the RS232 and
rS485

Answer / calvin

RS232 -
-- point to point
-- Distance 20m
-- Both Half duplex & full duplex
[half duplex --> Data can only be sent or received at
a time and not both same time]
[Full duplex --> data can be sent or received at the same
time]
-- An unbalanced signal --> represented by a single signal
wire where a voltage level on that one wire is used to
transmit/receive binary 1 and 0
-- min input level +/-3V
-- Very sensitive to noise

RS485
-- Multipoint
-- distance upto 1200m @ 100Kbps
-- only half duplex
-- min input level 200mV
-- less sensitive to noise

Answer / shahul

RS232
It is limited Distance and the speed is Maximum up to
19.2KBPS for 50 Feet.
only single ended.Only 1 transmitter/1 receiver
Supports only Full Duplex.
Signal level is unbalanced.
Higher output current 500mA
RS485
Multi drop topology and supports both half duplex and full
duplex.Maximum 32 Transmitters and 32 receivers.
Max.Distance up to 4000 feet with 100KPBS
Signal Level is Balanced.
Less output current.

Answer / dattatray naikwade

Differential signal voltage level is 0.2V for RS 485 where
as it is +/-3V for RS232.

Answer / gyani

mr.binu
if answer is so,why we need a protocal changer from RS232 to
RS 485? ethernet is used for 100 mtr.to 1 km.for more than
one km we use optical fibre cable,in this case also we need
protocall changer to convert the signal.please clear it.

Answer / jigar bhatt

*RS422 devices also operate Full Duplex.
*transmit&receive signal lines separate for bi-direction comm.

*RS485 operates in a half duplex manner.
*Devices operate as transceivers, but not simultaneous.

*RS232 is unbalanced(i.e Single wire is used to
transmit/receive binary 1 and 0) while RS485 is balanced(i.e
voltage difference is used to transmit/receive binary
information).

Officially the RS485 specification allows only 32 nodes
(devices) on the circuit. However, IC
manufacturers have developed RS485 drivers capable of
allowing 128 to 255 nodes on an
RS485 LAN. This means that you can use our Converters and
Remote I/O devices in more
expansive situations.

Answer / amit

RS232

1. single ended unbalanced line transmission
2. prone to noise
3. difference in ground level between T and R leads noise
4. Distance 50 Feet
5. Speed : 20 KBPS
6. Full duplex

RS422

1. differential ended balanced line transmission
2. no noise problem
3. Distance 100-4000 Feet
4. Speed : 100 KBPS to 10 MBPS depend upon distance
5. Full duplex/half duplex depend upon design
6. Point to point/ multidrop
7. Single transmitter and Receiver up to 10


RS422

1. differential ended balanced line transmission
2. no noise problem
3. Distance 100-4000 Feet
4. Speed : 100 KBPS to 10 MBPS depend upon distance
5. Full duplex/half duplex depend upon design
6. 32(max) transmitter and Receiver up to 1032

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