Hydro Logger H40
User manual
FIEDLER
electronics for ecology
11
2.3.
Power supply system
The Hydro-Logger H40 is powered by a lithium battery block, which guarantees many
years of operation of the device even when the measured data is transmitted to the
server via GSM/GPRS network on a daily basis. The instrument is supplied with an in-
serted battery pack and since the instrument has an extremely long operating time when
the parameters are set correctly, there is no need to replace the battery pack for the first
few years of operation.
A lithium battery pack with a voltage of 3.6 V and a capacity of 26 Ah is used to power
the Hydro-Logger H40G (basic version with built-in GSM module). The block is com-
posed of lithium batteries enclosed in a shrink wrap into a single unit and is equipped
with a short cable ending with a connector for easy connection to the electronic board of
the device.
The Hydro-Logger H40D without GSM communication module contains a smaller power
supply unit with a voltage of 3.6V and a capacity of 19Ah.
The K2 connector contains, in addition to the 485 data signals and the AV1 analog input,
a program-controlled supply voltage for the connected sensor. The magnitude of the
supply voltage is user adjustable from 6 to 15V DC according to the requirements of the
connected sensor or measurement probe. A lower supply voltage saves battery capacity.
The +Unap supply voltage is only present on pin 1 of connector K2 for a short period of
time when the station requests a new measurement. The magnitude of the +Unap supply
voltage, the frequency of the measurement and the supply voltage on time are adjustable
parameters.
USUAL OPERATING TIME
The system of active stations and a passive server allows the GSM module to be perma-
nently switched off and only switched on when the station requests to transfer measured
data to the server or to send a warning SMS. This concept also allows the station to oper-
ate for many years without changing the power supply batteries. In a practical test, the
H40G was tested to be able to perform more than 5,000 data sessions to the server (or
send the same number of SMS alerts) without changing the battery pack.
With a typical archiving interval of 10 - 15 minutes with one sensor connected via RS485
or analogue input, the H40G station can operate for more than 10 years without changing
the battery pack, while transmitting data to the Internet on a daily basis.
In addition to the power required for data transmissions to the server, the power supply
must also cover the power consumption of the measuring probe or sensor connected to
the station. However, this consumption does not consume even 10% of the total capacity
of the power supply batteries during normal use of the instrument and over 90% of their
energy is consumed for GSM data transfers from the station to the server.
The current drawn from the batteries is continuously integrated in the station and the
energy drawn is continuously subtracted from the initial capacity of the power batteries.
The remaining battery capacity is archived on the user-accessible control channel K13.
The time record of the declining battery capacity can in many cases explain the often
mysterious rapid discharge of batteries - for example, inappropriate parameter settings,
a fault in the connected sensor, cable damage, etc.
When the battery pack is depleted, the user can replace it himself in the field. The de-
tailed procedure for replacing the battery pack is given in the chapter "Service".
The Hydro Logger H40 is not designed for external power supply connection.
H 4 0 G
H 4 0 D
I n t e g r a t e d v o l t a g e
c o n v e r t e r
R e p l a c i n g d e a d
b a t t e r i e s
N o t i c e
