Bogart Engineering TM-48VA How To Connect

How to connect 48 volt adapter/lightning protector (TM-48VA)
(For use with TriMetric models TM-2020 and TM-2B that mount in "double gang" box)
Description: The TM-48VA adapter will adapt a TriMetric TM-2020 or TM-2B meter for 48 volt operation. It will also provide
excellent lightning protection at any operating voltage from 12 to 48V. With the protector installed as described here, the
TriMetric warranty will extend to cover lightning damage. This adapter is designed to mount next to the TriMetric terminal
block to which the wires to the battery are connected. It is not recommended for use with the older type TriMetric TM-1B,
with its smaller steel cover, because although it will work electrically and protect the meter, the cover will not fit on the
meter when the adapter is installed. A slightly different adapter is available (TM-48V) which may be used with the TM-1B.
Installation considerations for the TM-2020 meter which mounts in a "double gang" electrical box The TriMetric TM-
2020 will fit with the TM-48VA adapter inside the optional Wiremold "double gang" box (Wiremold #2348-2), but not with a
lot of extra space. The adapter mounts against the terminal block with short wires which connect the TriMetric to the
adapter--as shown on reverse--and both adapter and meter will fit in the box. Other "double gang" boxes may be used--
plastic or metal--however it is important to use one that is large enough to accommodate the extra space required by the
adapter. It may be necessary to bend the adapter up, no longer parallel with the TriMetric circuit board, but more nearly
perpendicular to it. An advantage of plastic boxes is that there is less chance of inadvertent shorts. However it is possible
to use a large metal box: 4-9/16 inches square by 2-1/8 with a raised 2 device cover, if you bend the adapter up somewhat
as just described and shown on reverse.
Installation instructions: Follow steps 1-5 on the back of this sheet.
Specifications:
Lightning protection spec: It is designed to absorb lightning induced transients with 100 Amp max. surge current (8 µs
rise/100 µs decay time). Under these conditions voltage may rise at the input to 200 volts for up to 1000 µs. (This is a
conservative rating.)
Maximum/minimum voltage allowed to adapter: The minimum and maximum system battery voltage which may be
placed to the adapter depend upon whether it is configured for 12, 24 or 48 volt systems. (See step 1 on reverse.) Too
high voltage will damage the unit; the voltage rating should not be exceeded, even for short time (except for the very short
lightning transients mentioned above.) Too low voltage will not damage the unit, however the TriMetric may not function
properly.
12 volt configuration: minimum 8 volts, max. 18 volts.
24 volt configuration: minimum 12 volts, max. 50 volts.
48 volt configuration: minimum 12 volts, max. 70 volts.
Power requirement: Requires less than 1 ma.
Other notes: Set the adapter for the correct voltage for your system. (Described in Step 1 on reverse). If the adapter is
configured for 12 volts and connected to a 24 or 48 volt system it will be damaged. If the adapter is configured for 24 or 48
volts and used on a 12 volt system the meter may not operate correctly if the system voltage drops below 11 volts. You
must also set the TriMetric to read properly for 48V, as described in STEP 4.
Calibration: (Step 5) With 48 volt systems, to obtain the best voltage accuracy, the following calibration procedure may be
carried out by a qualified technician with an accurate digital voltmeter. Without calibration, the voltage will be accurate to
±1%--however calibration can decrease this to ±0.3% for voltages between 40-70 volts. (If the adapter was purchased
from the factory with the adapter attached, the unit has already been calibrated for the 48V adapter supplied, and a
calibration similar to that described below will be necessary to increase accuracy if meter is used with 12/24 volt
systems.) You may first connect meter up to 48 volt system according to instructions. With power off, (remove fuse in +
battery line to meter at battery) take TriMetric out of its box, so the back of the printed circuit board is accessible. Locate
the small square adjustment "pot" (marked "P1") on the board, with small screwdriver slot in the middle, and obtain a
very small screwdriver suitable for adjustment. Get the whole arrangement set up so you can safely observe the meter
reading while adjusting the "pot" on the PC board. 48 volts is sufficient to deliver a shock, and can even be dangerous in
some situations. With TriMetric meter connected to system, restore power by reinstalling the fuse. Use the known accurate
digital meter to measure voltage between G1 and M+ terminals (on the battery/shunt side, not the TriMetric side i.e., you
should be measuring voltage across the battery) at the adapter input: Carefully adjust the pot so the TriMetric "volts"
reading agrees with the digital meter. Then remove the fuse again, reinstall the meter, and finally reinstall fuse.
19020 Two Bar Road, Boulder Creek, CA 95006 Tel:(831)338-0616
to the TriMetric battery monitor
Revised July 1, 1998
Bogart Engineering
48VadaptInstruct-VA.doc-