Saab TankRadar L/2
53
US Version. Seventh edition, June 1995
Installation Manual
12 Electrical Installation
Warning!
Isolate and terminate ends of unused wires. The intrinsic
safety may be jeopardized if any cable ends are hanging loose. Use certi-
fied battery operated instruments only. Use Saab Tank Control original
spare parts only.
Note:
For all electrical installation, please see the instructions in the
electrical installation drawings. See list of drawings in chapter 13.
12.1 Cabling for Power Supply
The cables used for the power supply connection must be suitable
for the supply voltage in question and also approved for use in
hazardous area where it is applicable. In the USA, for example,
explosion proof conduits must be used in the vicinity of the tank.
The wire areas must be selected not to cause too much voltage
drop on the way to the RTGs, the DAUs, the FCUs, etc.
Each Radar Tank Gauge and Field Communication Unit have a
switch for voltage selection that can be set to either 115 VAC or 230
VAC. Check that the switch is set in the right position before
power is connected. See chapter 3.1.3 and 6.3.
The selection of 115 or 230 VAC power supply for the Independent
Data Acquisition Unit is made by connecting a strap on one of the
printed circuit boards in the flameproof enclosure. See chapter
4.7.1. Maximum power consumption is 10 W.
The Slave Data Acquisition Unit receives its power via the local
line from the associated Radar Tank Gauge.
The power supply connection to the Radar Tank Gauge should be
made with wires according to table 12.1 below. The table shows
the voltage drop at various cable lengths and wire areas at the
maximum power consumption of 80 W. The figures shaded in
grey indicate combinations of lengths and areas that might result
in too high voltage drops.
1.5 mm
(AWG 16 or
similar)
0.75 mm
(AWG 18 or
similar)
1.5 mm
(AWG 16 or
similar)
115 V
230 V
Cable Length
0.75 mm
(AWG 18 or
similar)
100 m
330 ft.
3.1 V
1.6 V
1.6 V
0.8 V
200 m
660 ft.
3.2 V
3.2 V
1.6 V
500 m
1640 ft.
4 V
2
2
2
2
6.3 V
16 V
8 V
8 V
Table 12.1. Grey areas show too high voltage drop.
