Lightning Aresstors

[PA BEN]

On a URD Primery riser, witch side of the Cut out, high side between cutout and feed or buttom side between cutout and cable is best for the lightning aresstor? And why?

[OLE' SORE KNEES]

FPL puts them on the bottom near the terimation or ripple.Bottom side of switch.

[Pootnaigle]

Better to put em on bottom side That way if Lightning does strike the line the main line fuse wont blow taking out even more customers unnecessarily. Same protection either way

[shocker]

Better to put em on bottom side That way if Lightning does strike the line the main line fuse wont blow taking out even more customers unnecessarily. Same protection either way

are you serious?

[graybeard]

High side between the cutout and the line. If you make your jumper so it goe's from the line to the arrester to the cutout then if it gets a strike it should take out the arrester and not the fuse.

[KyLineman]

Better put them before the cutout on the feed side or you will start having problems with ferroresonance. If you have wye-delta transformers down stream they will cause problems when you are refusing or pulling them off. Also if there is wye-delta transformer down stream then all arrestors should be larger then the phase to phase voltage. Exp. we have 12470/7200 volt system and use 15kv MOV's on pad mount transformers that are wye-delta connected.

[scammy]

my understanding of ferro resinance is several transformers in line with long runs of cable,mostly 3 phase,,,nothing to do with arestors,,,,,,correct me if im wrong,,thanks scammy

[playtime]

my understanding of ferro resinance is several transformers in line with long runs of cable,mostly 3 phase,,,nothing to do with arestors,,,,,,correct me if im wrong,,thanks scammy

You are correct. but the imbalance of having a phase down is enough to cause arrestors to blow. Have blown arrestors when closing in fuse doors. First one is ok but the second one is when shite happens. It helps to have two guys closing in the last two fuse doors at the same time.

[hotwiretamer]

High side between the cutout and the line. If you make your jumper so it goe's from the line to the arrester to the cutout then if it gets a strike it should take out the arrester and not the fuse.

What protects your cable on a loop system when one of your feeder risers are in the open position?

[shocker]

the placement of arr. above or below the cutout will not create ferro res.that is a situation that involves inductive reactance and capacitive reactance,3 phase,long cable runs and little or no load on the trans.Arr's primary purpose is to protect equipment from over voltage damage.In a lighting strike to the conductor the closer the arr. to the line the better chance of bleeding off excess voltage.thats not to say the down feed fuse or even an up stream fuse still wont blow but the risk to the cable and euipment is reduced.a loop feed with one down feed open is an unusual config.but the other side still has arr. protection.