Weird lights in saber

[DLEE]

At the NAC in Sacramento the following occurred on one of the strips where one of the youth events was fenced: While approaching the on guard line and far from opponent, Fencer on the right (the green light) touches her lame with the bell guard and then Fencer on the left touches the metallic strip with her blade and gets a light (red).
Turns out that the reel on the right was pulled up over the edge of the strip slightly such that the metal underside of the reel was making contact with the metal strip. So when the reel was pulled away from the strip the fencer could no longer get a light by touching the strip.

The question is whether the reel touching the strip as described would have caused any abberrant lights during fencing in situations where the fencer's blade had not touched the floor? It seemed like there were a lot of odd lights in some of the bouts but that could have been a coincidence. Obviously an understanding of which line is which would be helpful but I can't figure it out.

[DJ Apostrophe]

A line = Target (lame in foil and sabre, one of the wires in the blade in epee)
B line = weapon (in sabre the B line is the weapon itself, in foil, it is the wire running up the blade, in epee, the B line is the other wire running up the blade)
C line = ground, in all three weapons, the weapon itself is the C line (in sabre, the B and C lines are connected together at the socket) (the strip is its own line when connected to the box... but behaves in much the same way as the C line).

What was probably happening is the case of the reel was probably acting as a B line....

in that case, shorting the weapon to the lame would create an A<->B&C connection at the lame, and the reel to the floor would be a B<->C short...

so when the lame was touching the weapon, you've connected the lame to the strip....

this situation (hitting the grounded strip and getting a light) if you took someone's mask and placed it on the strip while the headcord was still connected to the lame... then you've skipped the B line short of the reel and gone right for the A-C connection...

if the weapon was not in contact with the lame, i can't see how it would effect the lights... but someone more knowledgable than me might see something that i'm missing.

-w

[DHCJr]

Someone recently complained that the Favero reels did not have a place to plug in for the piste ground. This is the reason it is not there. Older designed reels have this, but they were designed before the anti-fraud.

The problem is the rules state the C line must connect through the case of the reel and the Uhlmann used at NAC's follow that rule. Because of the anti-fraud circuit the C of the weapon and the C of the piste are different lines. But what happened is they are now connected, so that is why it occurred.

Now the solution, disconnect the ground for the piste or make sure the reel is not on the piste. What bothers me is how this happened. The reel has rubber feet which should keep it away from touching and even if it were missing a foot the spring case should have kept it apart.

[DLEE]

The reels touching the strips appeared to be fairly common. In one of the Y10 saber pools the referee noticed a problem and had the reel moved. Generally the reel would just slide up to abut the strip but on occasion it would be pulled up over the edge of the strip such that the bottom part pf the reel touched the metal. The feet on the reels do not withstand the constant pulling on the cords. They stay in place much better if taped down.

[KD5MDK]

I was under the impression they were taped down. In fact, I distinctly recall brtech posting the clever and simple way to tape them down used at NACs.

[oiuyt]

I was under the impression they were taped down. In fact, I distinctly recall brtech posting the clever and simple way to tape them down used at NACs.

Doesn't mean they always are. Or all are. Or stay taped down.

At least some of the reels in Sacramento were not taped down (I had one that was walking sufficiently far to unplug the fencer on my right while I was refereeing the final day (or maybe day 3)). The floor cords did all seem to be taped down.

-B