2 – Installation
2-6
© Teledyne Limited
DPN 402197 Issue 7.1
of the M5 screw engages with the recess in the coil body. If necessary, tilt the assembly to the
left to prevent the coil falling from the groove.
7. Place a clamping block
B
against the coil and insert four M8 × 50mm bolts. Use a 6mm hexag-
onal key to tighten the bolts evenly until the block supports the coil properly.
Do not over
tighten these bolts
.
Fit the vertical coil:
8. Insert an M5 × 12mm screw into the vertical support groove that is farthest from you and use a
3mm hexagonal key to tighten the screw lightly.
9. Turn the vertical coil
E
so that the 8-way connector is at the top. Fit the coil to the groove so
that the head of the M5 screw engages with the recess in the coil body. If necessary, tilt the
assembly forward slightly to prevent the coil falling from the groove.
10. Place a clamping block
B
against the coil and insert four M8 × 50mm bolts. Use a 6mm hexag-
onal key to tighten the bolts evenly until the block supports the coil properly.
Do not over
tighten these bolts
.
This completes construction of the starboard coil triad.
Assemble the port coil triad in the same order. Note that the port coil triad is a mirror image of the
starboard:
❐
The lateral coil must be oriented and assembled with its 8-way connector pointing to the right.
❐
The fore-aft coil must be located in the left-hand side of the centre block during assembly, with
its 8-way connector pointing towards you.
2.2.2.2 Mounting the coil array
CAUTION
If you mount the 350 system on the same ROV as a TSS 440 Pipe and Cable
Survey System be aware that with the drive current applied to the search-coils of
the 440 system large induced voltages can appear across the sensing coils of the
350 system.
Later versions of the 350 sensing coils (serial numbers from 570 and upwards)
included diode protection to avoid damage to the coil pre-amplifiers. Refer to
for details.
NOTE
The accuracy of measurements made by the 350 system might degrade if any of
the following affect the characteristics of the electromagnetic field radiated from
the target:
❐
The proximity of any material that is more conductive than the seawater. This
includes a metal or carbon-fibre ROV frame.
❐
The proximity of any large magnet such as that of an actuator.
❐
The presence of any conductive material between the coil triads that electri-
cally shortens the coil separation distance.