Comments about Furman P-2400 IT Symmentrically Balanced Power Conditioner:
I have only been using this device for a couple of weeks and haven't yet been on location with it. So I haven't really put it through its paces yet. It did solve the hum problem I had, which is what prompted me to buy it at this time, but that particular problem could likely be solved without resorting to this expensive unit. I got this unit because of issues that can arise on location, including extreme situations such as running off a generator (which is the case where I would also want voltage regulation). But I can say that my setup is now absolutely silent, except for the music I create with it.
There is no voltage regulation. It was not advertised as having voltage regulation (just out-of-range shut-off) but it seems absolutely bone-headed to leave it out. I can now purchase, for example, a Furman P-2400 AR to get voltage regulation, and put it between the mains and the P-2400 IT, but the redundancy and waste involved is outlandish. Basically, the AR has everything in it that the IT has EXCEPT "half a transformer" and PLUS a small amount of extra circuitry to regulate the voltage (and associated taps on the autotransformer). So adding it will tie up 3 more rack spaces (one for ventilation) and make my rack case even heavier than it now is, plus cost me quite a bit more money.
At this price point, that functionality could easily have been included in the IT within the existing case size (3 RU) and with an insignificant increase in weight. All one needs is the taps on the transformer (on the primary side, so as not to require double sets of taps to keep the voltage balanced) plus circuitry to auto-set the taps to keep the voltage stable. Had I been the designer, I definitely would have designed it that way. (I am an electrical engineer with an Sc.D. from MIT.)
Another bone-headed feature involves the extra rack ears for attachment to rear rails. It's great that Furman included this essential feature, given the weight of this device. The problem is that the screws that retain the sliding rear ears require a screwdriver to tighten them. It is extremely difficult if not impossible to install the unit in a rack unless the rear ears are loose enough to slide. (Ok, maybe you could do it if you removed and re-attached the rear rails...) Once installed, I could not tighten the screws even with an offset screwdriver. There just isn't enough space in the rack. (And my rack case has generous side clearance.) I bought replacement screws with hex heads so I could tighten them with a wrench.
The NEMA 20P plug on the unit can be a problem. This may be due to electrical code compliance issues, as this device is a special case that is a bit awkward for the US NEC (National Electrical Code) language. It should be OK to use this device on a 15A circuit, for the same reason that it is OK to use a 20A extension cord on a 15A circuit. The actual load is determined by what you plug into it, rather than by the unit itself. Since a NEMA 20P plug can't be connected to a NEMA 15S socket, this could be a problem when using the device on location. Furman sells a short adaptor cord that allows you to connect the unit to a 15A circuit, or you can make one up yourself, as I did. Note that you CAN connect a NEMA 15P to a 20-amp circuit. Also, this unit would be NEC compliant if it had a NEMA 15P plug AND all the sockets on it were NEMA 15S, which would probably be just fine for anyone who ever uses this device.
Other than these complaints, all the other features of the P-2400 IT are as advertized and well implemented.
On the positive side, I should mention that all the outlets on this device are protected by GFCI, which is very important if you run with an isolated ground. The manual does not adequately cover the technical considerations and hazards associated with ground lifting. So be sure you know exactly what you are doing whenever you use the ground lift.
Not much to say here. The build quality looks absolutely excellent to me.
I think this device is seriously over-priced.
