Instruction Manual

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the second case. This is an important “bottom line” number of the battery system performance, as it is
a measure of total “storage utility” gotten from the batteries. This number is periodically stored every 3
hours in “non volatile” memory, which means that if power is removed from the PentaMetric, it will only
lose the last 3 hours of data at most.
Program modes that affect AD7, AD8, (Amps1, Amps2), similarly affect this display. Refer to section
AD7 AD8, for information about these program modes.
AD18, AD19, Watts1, Watts2: .
Program modes affecting data: P7, P8, P11, P12.
Watts1 is the product of volts1(AD1) and amps1(AD7). Watts2 is the product of volts2(AD2) and
amps2(AD8). (Reminder: Power, or “Watts” used by a load is equal to “volts” across the load times
“amps” through the load.) Watts are positive when measuring from a source, such as a solar array,
and will be negative when power goes into a load.
Program modes that affect Watts1 are affected by the same program modes that affect the Amps1.
(See AD7) Likewise, Watts2 is affected by the same program modes that affect Amps2. (See AD8)
Watts1 uses the same display label as “#1 Amps” (Program mode P7). Likewise Watts2 uses the
same label as “#2 Amps”.(Program mode P8) (Also, of course, watts is affected by the programming
of shunt type (P11, P12) as described in the reference for AD7-AD8.)
AD20,AD21 Watt hours1 (AD20), Watt hours2 (AD21).
Program modes affecting data:P7, P8, P11, P12.
Watt hours1 and Watt hours2 are the time accumulation of Watts1 and Watts2. Watt hours 1 and 2
accumulate watt hours continuously (positive or negative) for as long as the amps or volts channels
are not zero. Watt hours can be manually reset to 0 whenever desired by using the RESET button
while observing the Watt hours display. Refer to Section 4.A.1 “reset functions” for how the reset
button works.
Program modes that affect Watt-hour1 are affected by the same program modes that affect Amps1.
Note that watt hour 1 uses the same display label as “#1 Amps” (Program mode P7),. (Similarly for
Watt-hour 2) Also this measurement is affected by the programming of shunt type (P11, P12) as
described the reference for AD7-AD8.)
AD22, AD23 Battery Percent full 1 (AD22), Battery Percent full2 (AD23)
Program modes affecting data: P14, P15, P11, P12, P32, P33, P34, P35,.
This display keeps track of the amount of energy in the batteries, expressed as a percentage. This
number is based on the “battery capacity” number programmed in P12 or P15, and the number of amp
hours discharged from a full battery, in AD7 or AD8. For example, if 100 amp hours is programmed as
the “battery capacity”, and the “Amp hours from full” display is -25 amp hours, then this display will
show 75% full. It only has significant meaning when the corresponding “Amp-hour” channel has the
“battery” option selected, as described under AD13-AD15. For more detail about this function, see the
section:7 “How the PentaMetric keeps track of battery state of charge”
AD24, AD25 Days since charged, for batt1 (AD24) and batt2 (AD25)
Program modes affecting data: (mainly) P32, P33
These display how many days have elapsed since the battery(s) reached the “charged criteria” as set
up in program modes P32 and P33. Lead acid batteries should be periodically charged fully to enable
them to retain their maximum capacity. This display shows how many days ago they were fully
charged—expressed with a resolution of 1/100 day. An “alarm” function can allow you to set a
maximum number of days after which an alarm will signal to recharge the batteries. For information on
the alarm function, see section 6.E.4. Also see Section 7 “How the PentaMetric keeps track of
battery state of charge” to find out how the PentaMetric determines that the batteries are “charged”.
This display will be influenced by the numbers entered in “Battery charged criteria”, program numbers
P32 and P33.