To achieve the best performance from ALPHA-SORB (tm) transient protection devices, two parameters are matched.

1. Bus voltage must be at least equal to the buss voltage ( 12, 24 or 32 volt systems). Selection of the proper

voltage rating will provide the best transient protection.

2. Current rating for each voltage must be matched. Alpha Marine Systems offers -1 units designed for suppressing

the transients produced by low powered devices: pumps, etc. drawing less than 50 amps. The -2 units are designed

for high current alternators, motor generators and engine starters, all of which can produce transients particularly when

shutting down.


The use of the -2 high power units in low power circuits will not reduce the effectiveness of the protection.

It is just not as cost effective as proper matching. Use, however, of the low power -1 units in high current

circuits can cause an ALPHA-SORB (tm) or other system failure.

Proper application calls for:

1. Determining the source of the transient ( installation of the Alpha Marine Systems Trans-corder ( tm) will make this easy)

2. Estimate the maximum current drain of the device producing the transient and selecting either the -1 low current or

-2 high current protector.

3. Determine the operating voltage of the device producing the transient.

4. Select the power protection device form the table below and install the suppressor as close to the transient source as

possible. This will ensure maximum protection, reduce system noise and protect contactors and switches in the system.

On a typical vessel several transient sources may be found. Each should have it's own ALPHA-SORB (tm).

A less effective method of protection is to install a -2 device directly across the power input terminals of an instrument

to be protected. This may be the only way to provide effective protection. If this method is selected both Power and Ground leads must go directly to the ALPHA-SORB (tm) and no other grounds may exist as a current loop will be created which will bypass the protection device. Lead lengths must be kept short to eliminate lead inductance, thus ensuring the Full response speed of the device.


PART#     BUSS             TRANSIENT                 PEAK POWER     AVALANCHE 

                VOLTAGE     RESPONSE (NOTE 1)  WATTS                 VOLTAGE

AS12-1     12                 22.5V@ 67A                         18.2kw                 16V

AS12-2     12                 35.1v@ 128A                         54.6kw                 21V

AS24-1     24                 45.2v@33A                             18.2kw                 32V

AS24-2     24                 45.0v@ 67A                            36.2kw                 32V

AS32-1     32                 59.3v@ 25A                            18.2kw                 42V

AS32-2     32                 66.0v@ 86A                             36.4kw                42V


NOTE 1 Response time is typically 200 pico seconds ( 200 x 10 to the minus 12th power)

operating temperature is -40 deg C to 150 degrees C

Leakage current at rated voltage is less than 50 micro amperes.

Note 1; Transient responce 10x100 micro seconds. At 8x20 micro seconds the power rating is approximatly 10 times the above figures.

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