16
for detailed sounding of conductivity with depth it gives very useful results when the earth can
be approximated by a two-layer mode.
9. COMMUNICATON WITH EXTERNAL LOGGER
EM38-MK2 is designed to communicate with an external logger in two different ways: a)
through an RS232 serial port via cable connection or b) via a wireless Bluetooth connection. The
choice which to use will depend on the system configuration. For short (up to 10 metres) non
obstructed distances between the logger and the EM38, the wireless Bluetooth communication is
more convenient. For an application like instrument installation on the trailer, where there may
be obstructions between the instrument and the logger, an RS232 cable communication may have
to be used. Note that for proper communication with logger when RS232 port is used, a special
RS232 cable marked “EM38-MK2-4P” must be used.
The obvious advantage of wireless communication is there is no need for a cable and avoidance
of possible interference from the cable if the communication cable is moving around the
instrument sensors.
A more detailed description on the use of two communication method is provided in the EM38-
MK2 Logger Manual.
10. OPTIONAL COMPONENTS
10.1
External Battery
A provision is provided on the instrument front panel for use of an external battery. Depending
on the specific application, trailer mount for example, it may be convenient to use an external
battery to extend the battery service.
The external battery voltage should be between 9 to12 V. The required supply current is 50 mA.
To estimate the approximate service life of the battery, divide battery capacity in mA/h by 50.
For example a small fully charged gel cell battery with a capacity of 1.3 A/h (1300 mA/h) will
give approximately 25 hours of service. Note that the internal battery should not be removed
from the instrument even when the external battery is used.
10.1.1
External Battery Pack
The instrument can be supplied as an option with a rechargeable battery pack. The pack contains
a battery that when fully charged will last for about 25 hours of continuous operation.
To determine if the battery will require charging or replacing soon, the battery voltage can be
measured with a battery tester.
To check the battery voltage with a battery tester, insert the tester into the socket on the battery
pack panel.
Summary of Contents for EM38-MK2
Page 7: ...5 Fig A...
Page 23: ......
Page 24: ......
Page 25: ......
Page 26: ......
Page 27: ......
Page 28: ......
Page 29: ......
Page 30: ......
Page 31: ......
Page 32: ......
Page 33: ......
Page 34: ......
Page 35: ......
Page 36: ...34...
Page 37: ...35...
Page 38: ...36...
Page 39: ...37...
Page 44: ...42...
