# PLC -UART-12V technical questions‏ **URL:** \ **Category:** SparkFun Site Questions/Comments\ **Created:** [December 2, 2009, 5:27am UTC](https://community.sparkfun.com/t/plc-uart-12v-technical-questions-8207/13497 "2009-12-02T05:27:32Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![TLH](https://avatars.discourse-cdn.com/v4/letter/t/919ad9/32.png) [@TLH](https://community.sparkfun.com/u/TLH)\ **Post date:** [December 2, 2009, 5:27am UTC](https://community.sparkfun.com/t/plc-uart-12v-technical-questions-8207/13497/1 "2009-12-02T05:27:32Z")
Q1 - We like to connect the modem in the shown picture to test the data transmission (before we connect it to the power meter). we have connected as shown for data 2 to 3 , 3 to 2 and 5 to 5. Pls comment if there is any other connection or what we have done is sufficient. Q2- Do we need additional external 12 VDC power supply to power up the module? (we bought PLC-UART-12V). what is the max watt for the circuit board. basically we dont know what is the supply current. Q3- We are using DC power line as the transmission media for data. Advise if we can use the same source of power supply for both external power supply and transmission. ---
**Author:** ![n1ist](https://avatars.discourse-cdn.com/v4/letter/n/5daacb/32.png) [@n1ist](https://community.sparkfun.com/u/n1ist)\ **Post date:** [December 3, 2009, 6:33pm UTC](https://community.sparkfun.com/t/plc-uart-12v-technical-questions-8207/13497/2 "2009-12-03T18:33:13Z")
This is all answered in the docs. Q1: If you have SEN-09082 installed, those 3 pins should be sufficient Q2: 12V@100mA minimum Q3: For DC power, you can use the same supply for both power and operation as long as it is a 12v supply. Make sure you set the SW\_1\_1 jumpers correctly. /mike