I very much appreciate Rick's comments re: design differences in equipment
used aboard ship, and the problems attendent to supressing radio
(RFI). It is certainly true that all equipment
isn't equal and that European CE standards help to ensure somewhat "better" designs.
That said, however, I'd like to point out that there ARE significant differences among equipment types generally available on the U.S. market. Over many years, I've had occasion to work with a variety of marine
chargers and related equipment aboard my own vessel and in my shop at home. Since I'm an avid ham with far more radio
and test equipment than is reasonable, including a purpose-made RF sniffer, some of the following may be of interest to illustrate how equipment can differ, even in the same environment
1. Old Heart Interface Inverter/Charger, 1200 watt modified sine wave inverter
, 40-50A smart charger
. I've had this unit for 17 years, 16 of those aboard my boat. It is presently in my shop being used for a pulsator test with golf-cart batteries. This unit puts out a considerable amount of RF in both the charger
modes....enough to interfere with HF communications
. But not VHF/FM.
2. ProMariner 10A smart charger. Six years old. Installed aboard my boat in forward cabin
to keep dedicated golf-cart battery
bank for windlass
charged. This unit creates considerable RF which interferes with HF reception
when it is under load. When the load is small, e.g., in the float mode, RFI is negligible. No problem with VHF/FM ever. It also has an annoying loud fan which runs periodically even with a moderate ambient temperature and when in float mode.
3. ProMariner 50A smart charger. Age unknown (borrowed for ongoing test in my shop). This is the previously mentioned unit which created enough RFI via the 115VAC line as to cause a crash of my LAN and cause my computer monitor
to jiggle wildly (when under load.) These problems are not present when the charger is under a minimal load. However, it has a noisy fan which runs periodically even with a moderate ambient temperature (65F) and no load (float).
45A smart charger with IQ4. I've had this charger for almost three years. It maintains a golf-cart battery
bank which powers my radios at home, in a setup very much like shipboard. This is a high-quality charger which creates very little RFI. My radios are very happy when this unit is running. In previous technical discussions with a knowledgeable supplier, I've learned that the underlying technology is pulse charging
....a highly desirable way of charging
batteries. I'm attempting to confirm this with engineers from the Iota
factory. IMHO, this is the finest battery charger available at modest price
; it comes in several versions, up to the 90-amp model which Sully uses very successfully.
5. Victron 2500W pure sine wave inverter with 120A charger. This new unit was installed on my boat about 4 months ago. It is manufactured in Holland
to an exceptionally high standard. When I took the cover off, I couldn't believe the quality of construction....I've never seen anything like it, even with much of the military standard equipment I own. I LOVE this charger/inverter. No RFI. No noisy fan running unless it's under a significant load. Fully programmable. Unfortunately, Victron had a dingbat rep here in the U.S., recently dropped, so the equipment isn't very well known here. It is popular in Europe
6. Xantrex Echo Charger, 15A. This little inexpensive device keeps the starting battery charged automatically, whenever it senses a charging voltage on the house batteries (all charging sources aboard my boat...alternator/diesel generator/Victron battery charger....are connected to charge the house battery bank). Trouble free for past two years since installation
. Little or no RFI detected.
Think that's enough for now.
Bottom line: choose your equipment very carefully. It IS possible to find the stuff you need which will create low RFI on your boat.