Product Announcement: 120 Ampere SI-Series ACR is Enthusiastically Received by the Marine Market

Since its introduction in November 2006, the 120 Ampere SI-Series ACR has been enthusiastically received by OEMs, distributors, and installers. Many customers see the value of automatically combining battery banks during charging, and isolating battery banks when not charging. (Click to read application briefs explaining automatic charging relays). What makes the SI ACR so popular is an additional feature—its ability to temporarily isolate House and Start battery banks during engine cranking to protect sensitive electronics.



Protecting Sensitive Electronics. Engine starting causes voltage sags and spikes in the starting circuit. These spikes may propagate to the House circuit. The size of spike appearing in the House circuit depends on how the House and Start circuits are connected together, and the layout of the system wiring. If engines are started while batteries are combined, the resulting sag or spike may be felt in the house circuit. These transient voltage levels may reset GPS and other navigation equipment, and may damage some electronics. Click for an application brief on overcoming dropout using the SI feature.

Damage to house electronics from sags and spikes caused by engine starting is a common problem encountered by marine electronics manufacturers and installers. The SI-series ACR has proven to be a good solution.

Case Study. Fred Fritz Electronics in Northern California is an authorized distributor and installer for Raymarine and other marine electronics manufacturers. They have dealt with damage to marine electronics caused by engine starting spikes for many years. In fact, Fred Fritz created his own version of start isolation before the SI ACR was available. According to Fred Fritz: “There is a current spike from starting. It’s especially visible with large engines; you can see it with an oscilloscope. These spikes usually cause failures in power supplies of electronic equipment. The damage caused by each spike is cumulative, building up and leading to failure.” Since the application of start isolation feature by Fred Fritz Electronics, warranty repairs have dropped off dramatically. “We’ve never seen a failure on a boat with an installed SI-Series ACR. We used to have a thick stack of warranty repairs caused by these failures; now we have less than 5 per year, and none of these failures are on boats equipped with starting isolation”, he added. Fred Fritz Electronics has installed a large number of SI-Series ACRs.

High Current ACR. Building on the success of the SI ACR, starting isolation is being incorporated into the upcoming Blue Sea Systems high current ACR. The ML-Series ACR has a continuous rating of 350 Amperes, three separate start isolation circuits, and remote emergency cross connect; and will be available early in 2008.

Companion Battery Switch. A natural companion to the SI ACR is Blue Sea Systems award winning Dual Circuit Plus™ Battery Switch. The Dual Circuit Plus™ Battery Switch isolates engine and house circuits, and combines battery banks for emergency starting.

For more information about these and other battery switches, look in Blue Sea Systems 2008 catalog, or go to www.bluesea.com.