Instruction Manual

13
1.F: Relay output control:
It provides for control of a relay that: (1) turns “on” when the battery voltage drops below an “on” set
voltage or when the state of charge of the battery decreases below an “on” setpoint. and
(2) turns “off”
when the battery voltage rises above an “off” set voltage, or when the state of charge of the battery
exceeds an “off” setpoint This could be used to control a generator or external alarm . It is also
possible to reverse the logic, so that the relay turns “off” instead of “on” as the voltage drops below the
setpoints and goes “on” when it goes above them. For technical relay information see section 2
“Relay Output control”. For detailed description of setup possibilities, see section 6.A under
P30-P31.
Section 2: Some information you should know before installing
the system
Shunt requirements
Shunts are required to measure current (amps) by this meter. These are large, precise, very low
resistance resistors that convert “amps” to “millivolts” that the meter reads. One shunt is needed for
each “amps” channel, up to a maximum of 3. They must all be wired in the negative side of the battery
system “in series” with the wire or cable whose current you wish to measure. The wiring diagram
(figure 1) shows numerous possible locations for the shunts, depending on the application.
There are two types of shunts that you may use depending on the range of current you need to
measure. All 3 need not be the same type.
500A/50mV shunt:
The PentaMetric can measure from 0.1 to up to 1000 amps with the 500A/50mV shunt--but shunts
of this type are usually limited to 400 or so continuous amps before they overheat. This assumes
they are connected with 1 ft (or more) of #0000 copper cable at each end to conduct away heat
(and of course, electricity).
100A/100mV shunt:
The PentaMetric can measure from 0.01 to up to 200 amps with this shunt--but shunts of this type
are usually limited to 75-100Amps continuous before they overheat. This assumes they are
connected with 1 ft (or more) with #4 wire to conduct away heat.
Other shunts
If you have a very small battery or battery system it is also possible to use other shunt values. For
example, a 10A/100mV shunt could be used if the system is measuring a small battery where an
“amps” range from 1mA to 20 amps would be desired. In this case the user would have to mentally
divide the “amps” and “amp hour” readings shown in the PentaMetric by 10.
Decide on the shunts you need, depending on what “amps” measurements you require. Most
systems with one battery system would usually have one shunt placed to measure battery current.
(shown as “shunt 1” in figure 1). Another could measure solar input (“shunt 2”), or other charging
source (“shunt 3” or “shunt 4”) to be able to measure daily input power. The diagram shows a number
of possible shunt locations for these. The shunt itself is “bipolar” and can be installed in either
direction. However the wires from the PentaMetric input unit must be connected on the correct “Kelvin”
terminals, according to the + and - signs as shown. The “+” terminal is the one electrically closest to
the battery minus terminal. This will insure that “charging” amps appear as positive values, and
“discharging” amps as negative ones. Before wiring it is advisable to make a wiring diagram for your
system. You might want to use a red pencil to draw in the shunt connections on the figure 1 wiring
diagram before installation.
If one battery system is being monitored, the battery shunt (“shunt 1”) should be connected to
“#1Amps” channel, and the terminal from the battery positive post should be connected to the Volts1
input. The “volts1” input also supplies power for operation of the PentaMetric system. The meter must
always be supplied with voltage here (minimum 9 volts) for meter operation, and if data is to be