if the t/c o/p is 4-20mv then how plc recognize it
because we are dealing with the 4-20ma in the
plc ????????????????
Answer Posted / arindam
why we require a 4-20 mamp for transmission? the main reason
behind it because of electro magnetic interference the
voltage can get interfered very easily and we can't get our
desired o/p value.when we are using 4-20 mamp this problem
is solved but since, PLC is a digital device it can
understand mainly High=5V or low so we design the sink to
have a resistance as high to get the desired voltage, the 4
mamp is also helpful to power the electronics at the
transmitter end. to have a 4-20 mv instead can firstly :
cause em interference and secondly we need to have a
continuous level monitoring for different voltages...which
can increase the size of PLC . Also because of change of
impedance at the transmission line the voltage can drop
below 4 volt ocassionaly then loop powering of field
instrument will not be possible.
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Yokogawa CENTUMVP R6.09 unable to download to Engineering Station with ExaOPC R3.75
The issue is when I try to download the common project section to the Engineering Station (STN) from the HIS in System View, it is unable to connect. The error displayed is:
WARNING: Could not connect to equalize destination. (7001)
Retrying. Number of retries = 0/1
ERROR: LdXopsLoadMain: connect error 10060
ERROR: Processing terminated due to connection error. (7002)
Equalization end with errors. STN0149
---- ERROR = 2 WARNING = 1 ----
Background:
>Updated the ExaOPC software on the STN from 3.60 to 3.75
>STN operating system is Windows Server 2008 R2
>HIS operating system is Windows Server 2016 Stanard
Solutions attempted include:
>Ensuring all IP addresses are correct and all networked devices can be pinged.
>The ability to ping a device using its host name from another device (
hye SAM acn u send your e mail id, so that i can solve my query through e mail?
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