Assuming your utility is like mine (Springfield, IL) they'll be stubborn, so make them learn the hard way.

Assuming your utility is like mine (Springfield, IL) they'll be stubborn, so make them learn the hard way.

Is Ameren Illinois your Utility?

Yes.

Yes.

I have found 2 GE M400R3 Luminaires that are about 4-5 years old.  They are rated for 400W  and were both recently relamped.  Now, neither of them warm up to the full 400W that they are supposed to put out.  Any one of us streetlight geeks  would be able to tell.  I think they are putting out about 300W worth of light each.  I find this absolutely amazing that both of them are doing the same thing.  They started cycling about 6 months ago at the same time, and were re-lamped at the same time.  I have narrowed it down to a few suspec causes.

1) they both have faulty capacitors
2) there is a bad ground
3) they both have the wrong lamp/faulty lamps.

I just find it odd that 2 separate luminaires are doing the exact same thing.  I would love to get up in a lift and investigate.. 

What say y'all??

Not to steal your Thunder, but I think it's called an m400a2, not R3.

Only in Europe this is ok

Not to steal your Thunder, but I think it's called an m400a2, not R3.

Nope, it is an M400R3.  These do not have the PowrDoor feature, and they have the "round box" look of the AEL 125.  The M400R2 is still produced alongside them

Well, it took me some time, but I have re-visited the new luminaires, this time in the daylight.  Turns out, they are 250W PSMH (not 400W), but they have 400W HPS lamps installed.  So I figured out why they don't reach full intensity.  If there were 250W HPS lamps installed, it would reach full intensity.  I can only assume that the linemen didn't pay much attention to the NEMA label, or didn't have any 250W PSMH/HPS lamps on the truck, and only had 400W lamps.  I assume they figured if it worked, they would leave as is for now, but when the time comes to re-lamp, they may put the right ones in.

The 250W HPS will most likely cycle there, as they would be overdriven and with too low OCV for their operation (if the ballasts are 250W pulse MH).
So they put there the 400W HPS, as at least that means it will not cycle (underdriven HPS has lower arc voltage, so likely the ballast is able to hold the arc).
I only wonder if they think it is compatible (because it won't cycle), or because they have excess of 400W lamps, but want to use just no more than 250W per fixture, so they have found some 250W pulse MH ballasts and have chosen this combination just to "make some use of the lamps"...

I can't imagine it would be just to make use of the lamps, as there are plenty of 400w HPS fixtures around.  And it's just these 3 that are 250W PSMH.  The other M400R3s around here are 400w HPS.  I think you may be right though about them just finding some PSMH ballasts, as for just a little while, they were installing them and now they are back to HPS only.

I don't really mean to ask the question as it is typed, as I know for a fact that it can, however, Ameren Illinois recently installed (3) GE M400R3 with the White/Red 40 NEMA Label, which is the Label for PSMH, but they put 400W HPS Lamps in the fixtures instead of 400W PSMH Lamps.  These are brand new luminaires, probably no more than 4 months old, and all 3 are pretty dim.  I'd say, if I had to guesstimate, that the light output from each one is between 200-250W of light.  Now, there is also a single GE PF-400 with the White/Red PSMH NEMA Label (40) and there is a 400W HPS lamp in that fixture as well, and it warms up to the full intensity.  So I guess my REAL question is, Will it cause damage to the Ballast/Capacitor/Ignitor  to run a 400W HPS Lamp in a 400W PSMH Luminaire?  Because, as I said, it works fine in the PF-400, but the M400R3s, ALL 3 of them, do NOT warm up to their full intensity.  If it were only one of them that were like that, I would assume it is a fixture issue, but all 3 were installed on the same day, and all 3 are rather dim considering they are supposed to be 400 Watts.  I know full well that it is not putting out 400 Watts worth of Light.  The picture I attached is the label on all of the luminaires I have mentioned, except they read 40 instead of 25.

The reason why the 400w HPS lamps were underdriven on 400w PSMH ballasts was because 400w HPS lamps run at 100v and 4.5a while 400w US PSMH lamps run at 130v 3.25a.

Only in Europe this is ok

At least 400w European PSMH lamps seem to function as high CRI retrofits to 400w HPS ballasts since they are electrically interchangeable with each other.

150 S55 or S56 ?

In the US, 150w HPS is actually BOTH: the S55 lamps run at 55v 3.2a while the S56 lamps run at 100v 1.8a and are interchangeable with M102/M142 150w PSMH lamps and European 150w HPS and MH lamps.

And back to the original question, a hyporhesis: The fact two lanterns start to cycle at the same time may suggest they are connected to differrent (opposite) phase leg each and the common Neutral broke or has a bad contact. That leads to two 120V ballast connected in series to 240V. Not stable configuration, so does yield cycling. The use of higher power rated lamps lets them to operate at lower arc volrage, with way greater headroom towards the OCV, so allow the system to gain the stability even without the Neutral...

Would it be ok to run a 250 watt PSMH bulb on a 250 watt HPS ballast?