Banner DF-G1-PR-Q7 Instrukcje Operacyjne Pobierz pdf (Strona 123)

350 Cable Survey System

DPN 402197 © TSS (International) Ltd Page 12 of 30

7.3.2 Internal Logging Format

Data packets transmitted by the SEP fall into two categories – ‘co-ordinates’ and ‘sig-

nals’. The SEP transmits them sequentially so that either packet ‘A1’ or ‘A2’ below

immediately precedes packet ‘B’.

A1) Co-ordinates Data Packet – Survey mode

The string is 23 characters long with individual field definitions as follows. The SDC

logs all distances in units of centimetres and skew angles in units of degrees. The val-

ues in the packet are rounded and it is possible that they will not precisely match

those on the Run Display screen.

Table 7–5: Internal logging format – Survey co-ordinates

Notes:

1. The Start character is a colon.

2. The number of coils in the 350 System is always 6.

3. Coil altitude (ALT) information comes from an altimeter if the System includes one.

Otherwise, the information in this field will be the fixed coil height if available. If

there is no altitude information available the field will contain three space charac-

ters and a zero.

4. The lateral offset (LAT) is measured from the centre of the coil array. Positive val-

ues indicate a target to starboard of the centre line. The field will contain question

marks if the target is out of range.

5. The vertical range to target (VRT) is the distance between the reference line of the

coil array (identified in Figure 3–2) and the target. The value is always positive.

There are several conditions that will cause the field to contain question marks:

❐The target is out of range

❐The 350 System cannot compute an accurate position for the target

❐Coil saturation has occurred because the tone signal is too strong

1 2 ... 118 119 120 121 122 123 124 125 126 127 128 ... 252 253

Brak uwag

Banner DF-G1-PR-Q7 Instrukcje Operacyjne Strona 123