TM-2030 Technical Manual
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you must know the amp-hour capacity of your battery system which has been set in program P3. We often suggest value for the “current
setpoint” setting that is 2% of C, which is the default setting when the meter is new, where C=battery system capacity in amp-hours that is
programmed in P3. For example if you put =700 amp hours into P3, then a P2 amps setting of 2% would be 2% of 700 = 14 amps. Better
charging would result using 1% of C or even 0.5%, for the battery to be really charged—however this may require more solar time (for
example) than is usually available. If you are in complexity levels L1, L2 or L3, when you enter the current setpoint the TriMetric will
require that simultaneously both the filtered voltage setpoint be equal or exceeded, and the filtered current (amps) value be less than or
equal to the current setpoint before the TriMetric will indicate that the batteries are “charged”. In level L4, further requirements need
be met, as described in the SC-2030 Solar Charger manual. The “filtered” values are very sluggish versions of these parameters—
explained in Section 6.2 step 5. Also, if you are set to complexity level 3 or 4 (using Program P7) you can observe these filtered values of
amps and volts. To do so, when observing either amps or volts, when you hold the reset key down the filtered value will show in the
display.
Usually in float mode? Another possibility we should address is if your charging system stays much of the time in "float" mode, which may
be true for a “line tied” system, or a battery system in an RV that is only occasionally used, with its battery usually connected to a charger
that maintains it at “float” voltage . With a lead-acid liquid electrolyte battery the "float" voltage may be 13.4 volts (for 12V system) For a
system that is usually in “float” mode, the TriMetric voltage setting can be just below 13.4, (or whatever the float voltage is) and the
"amps" setting can be for some low value, such as C90 or so, or to a value which the "amps" would only go below during the "float"
condition. Then the TriMetric will reset only after the "float" condition is attained.
P3: Battery assumed capacity. This is the basis for calculating the Battery % full number. The Battery % Full is
calculated as = (Capacity – AmpHoursFromFull) ÷ (Capacity), expressed as a percentage. The Capacity (in amp hours) is
what you program in here. The AmpHoursFromFull is the value shown on the secondary display group. Also see the
“Installer’s instructions for TriMetric TM-2030” section C, under program item P3.
P4: Watt/Amps choice. Select which you prefer as your primary choice. Explained on Table 2.
P5: Days before “time to recharge” Battery reminder. Explained in section 2.2.1 and Table 2.
P6: Days before “time to equalize” Battery reminder. Explained in section 2.2.2 and Table 2.
P7: Operating Levels This allows switching to any of four Operating levels: L1=simplest, and OK for most users. L2= All
of L1 plus allows viewing History Data information. L3 and L4: All of L2 plus many additional programming options
shown below. L4 also redefines “charged” criteria. See section 3.
The following program items are available when the TM-2030 is switched to L3 or
L4 level. Use program P7 to select L3 or L4
Program modes P8, P14, P15, P16, P20, P21 and P22 are only used only with the optional SC-2030 charge controller.
See SC-2030 Solar Charger User’s Manual: Section 6.4 and profile graphs for exact descriptions.
P9 and P13: Audible Alarm. How to turn on or off. First be sure to program P7 (above) to “L3” (or
“L4”). Activate audible alarm by programming P9 so it is NOT ‘OFF” but has a number. Adjust the number for
“Percent full” below which you want the alarm to sound. We suggest 50 to start. Then go to program P13 and program a
battery voltage below which it will sound. (Suggest 11.4 for a 12V system—22.8 for 24V.) Then the alarm will sound if
the volts go below 11.5 or the % Full goes below 50%. When the alarm comes on it may be silenced by the reset or select
button--but the alarm's presence will still be indicated by the flashing "BLo" in the display window.
P10 Assumed charge efficiency factor:
Purpose of data: "charge efficiency factor" See section 6.2 step 4 for an explanation of “charge efficiency factor”.
Choosing values of "charge efficiency factor": In the “L1” mode this value is fixed at 94%. If you wish to adjust it to
a different value you will need to switch to “L3” mode. The actual "charge efficiency" factor for lead acid batteries
while they are not at the top of charge is generally higher than 94%, so this will usually give a conservative value for
"amp-hours from full"-- that is the meter will generally slightly under-estimate the “% Full” value for the batteries
which will give a useful practical result for knowing state of charge.
Optional technical note: Some people familiar with batteries will be surprised that the suggested "efficiency factor" is as high as 94%. Without going
into all the details here, there are two reasons for this: (1) The number entered in the TriMetric is not true battery efficiency, or energy efficiency,
(which is often quoted at 70-80% for lead acid batteries) but charge efficiency. Charge efficiency (the ratio of total amp-hours you get out divided
by total amp-hours to charge the battery) is always greater than energy efficiency. (2) What is entered in the TriMetric is not even the overall charge
efficiency of the battery, but the charge efficiency while the battery is not at the top of charge, and not gassing. A battery is not charge efficient
while at the top of charge, so if this part is excluded the battery is very charge efficient. (We have measured this to be 95-98% with Trojan wet cell
batteries.) Also note—when batteries are given a good, adequate charge they will not show up with very high efficiency.
P11: Shunt type: This must be set according to the shunt type you have. This determines the sensitivity of the "amp"
input to the TriMetric, so that it reads correctly for the shunt you have. If your "amps" readings appear to be off by a
factor of 10, the most likely cause is this that is not set correctly for your shunt.
Choosing value of "shunt type". At L1 level this is fixed at the more common 500A/50mV shunt. The 500A/50 mV
shunt is specified by “Sh H” (“High current shunt”) If you have a "100A/100 mV" shunt, you should enter Sh L
("Low current shunt"). Only the ratio shown is important to the TriMetric, so that from the TriMetric's point of view a
200A/200 mV or 300A/300 mV shunt is equivalent to a 100A/100mV shunt.