Rodneywagr
Electrical
Does anybody make PLCs which operate from a power supply of 48V DC, and which have inputs which accept 48V DC signals??
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48VDC PLCs
- Thread starter Rodneywagr
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dbaird
Electrical
- Mar 31, 2000
- 412
Are you sure you want 48 VDC inputs? Most solid state devices I am familiar with operate 10-30 VDC range. So unless you are using "dry contacts" I would investigate the wisdom of this.
David Baird
dbaird@gemcity.com
Sr Controls Engineer
EET degree.
Journeyman Electrician.
David Baird
dbaird@gemcity.com
Sr Controls Engineer
EET degree.
Journeyman Electrician.
- Thread starter
- #3
Rodneywagr
Electrical
In the installation, all the surrounding equipment works off 48VDC. The only power supply available is 48VDC. To use a standard 24V PLC will mean a DC-DC converter - another piece of equipment that can fail! Hence, if there are 48VDC PLCs available, the installation would be a little simpler. (and I prefer the KISS principle!!)
Allen Bradley PLC-5 line includes 48 volt dc I/O. The actual power supply to the PLC will have to be either 120VAC or 24 VDC. Check out their website
Check with these folks:
The acronym PLC may represent different equipment used in the electric industry. For instance “Programmable Logic Controlled” or “Power Line Carrier”.
In case this question was related to power line carrier, we would like to add that there are several utilities that require 48 vdc power supply source for the PLC used for communication, voice and data transmission. Few years ago we installed a PLC manufactured by ABB that operate at 48 Vdc.
To minimize cost in battery, chargers panels, etc we proposed a 48 Vdc using a 125 Vdc/48Vdc converter connected to a redundant 125 Vdc auxiliary system. This proposal was rejected from the utility communication department because the standard practice from 1940’s is to have a dedicated power supply source for PLC not related with other subsystems.
Today, with the availability of DC/DC converter technology, the facility of other redundant communication systems such as telephone, GIS, microwave, radio, etc., a dedicated 48 Vdc system is technically feasible but, could be questionable from the economical, reliability and maintenability point of view.
.
In case this question was related to power line carrier, we would like to add that there are several utilities that require 48 vdc power supply source for the PLC used for communication, voice and data transmission. Few years ago we installed a PLC manufactured by ABB that operate at 48 Vdc.
To minimize cost in battery, chargers panels, etc we proposed a 48 Vdc using a 125 Vdc/48Vdc converter connected to a redundant 125 Vdc auxiliary system. This proposal was rejected from the utility communication department because the standard practice from 1940’s is to have a dedicated power supply source for PLC not related with other subsystems.
Today, with the availability of DC/DC converter technology, the facility of other redundant communication systems such as telephone, GIS, microwave, radio, etc., a dedicated 48 Vdc system is technically feasible but, could be questionable from the economical, reliability and maintenability point of view.
.
jbartos
Electrical
- Jan 15, 2000
- 6,440
Suggestion: Visit
and type PLC under Product or Service which will return PLC related category
or type Controllers: Programmable Logic (PLC's) which will return 94 companies to inquire about your particular project PLC product availability
and type PLC under Product or Service which will return PLC related category
or type Controllers: Programmable Logic (PLC's) which will return 94 companies to inquire about your particular project PLC product availability
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