“O” RING MAINTENANCE
Novatech strongly recommends that “O” rings be serviced on a regular basis
to ensure a reliable seal.
Remove and lubricate at least once a year or
sooner and replace every two years or sooner
. With regular maintenance,
“O” rings will be very reliable and trouble free. It has been, however, our
observation that most “O” rings are neglected for years and expected to
perform at the extremes of their design limits.
There are two “O” rings and a Cup Seal to service. The “O” rings are at the
top end of the Pressure Case and on the Pressure Switch, the Cup Seal is on
the Pressure Switch. Replace the two “O” rings with Parker #218 or
equivalent available from Novatech or your local “O” ring supplier. Lubri-
cate lightly with a silicone grease, we recommend Parker Super O Lube.
Instructions for the lubricating or replacing the Cup Seal are below.
PRESSURE SWITCH CUP SEAL
The Cup Seal must not be overlooked when lubricating the “O” rings. The
Cup Seal should be lubricated every year and replaced every two years or
sooner. Lightly lubricate the Cup Seal by performing the following procedure:
Disassembly
1. Remove the two socket head cap screws on the Zinc Anode.
2. Withdraw the Zinc Anode and the black “Delrin” Knob Carrier.
3. Make sure the PS-200 Pressure Switch is in the
upright position
(Cup Seal up, spring down); this will make sure a small internal pin
will not fall out.
Do not lose that pin.
4. Carefully pry off the rubber Cup Seal, do not scratch the Cup Seal or
the mating “O” ring surface.
5. Observe the S.S. Flat Spring and note how it is installed.
Lubrication
1. Clean all surfaces and the Cup Seal.
2. Lubricate (very lightly) the “O” ring shaped portion of the Cup Seal
and the mating aluminum surface with silicone grease (Parker Super O
Lube).
Do not spread the silicone grease anywhere else. Excess
silicone grease can cause the Pressure Switch to fail
.
Reassembly
1. Be sure the small pin is in place
2. Place the Stainless Steel Flat Spring back in its correct position
3. Install the Cup Seal and rotate the Cup Seal ¼ turn to make sure it is
seated correctly
8
ST-400A
INTENSITY SETTING
EFFECTIVE INTENSITY
(Candelas)
RANGE
nautical miles
MINIMUM
6
2.0
FACTORY SETTINGS
20
3.0
MAXIMUM
35
4.0
Table 1. Effective Intensity measured in Candelas (estimated)
BATTERY LIFE
The following graph (Figure 2) may be used to estimate the approximate
battery life for different flash rate and intensity settings. Your actual results
may vary since we have assumed 1 day is 12 hours daylight, 12 hours
night. (ST-400A operates 12 hours per 24-hour period). Your actual day to
night ratio will depend on the season and your location.
5
ST-400A
