Using Watt's Up
16
7.4
Resetting Meter and Clearing Accumulated Values
All accumulated readings including Ah, Wh, peak current, etc. can be reset to zero in one
of two ways.
1. Completely remove all voltage from the Source's Red AND the Auxiliary Connector's
Pin 2 or,
2. On meter versions 2.1 and above, briefly (e.g. a thousandth of a second) connecting the
Auxiliary Connector's pin 3 to zero Volts. E.g. pin 1 or the meter's black wire. Meter
versions prior to version 2.1 do not have the Pin 3 reset capability.
Note that the meter will be held reset and not function if the reset signal (pin 3) is
continuously connected.
Pin 1 is the pin farthest from the Watt's Up SOURCE wires. Pin 3 is nearest the SOURCE
wires.
Pin 3 has a 3.3K Ohms input impedance.
See diagrams below to understand the reset function connections.
7.5
Connection Diagrams
The following diagrams show example connections between the Watt's Up and various
Sources and Loads using a "four-wire" connection.
A
"three-wire" connection
only connects the meter's red (plus) lead at the LOAD or the
SOURCE, but not both. A separate wire must be present to make the SOURCE to LOAD
(e.g. battery to speed control) connection "around" the meter. The advantage of the three-
wire connection is that only the meter's black wires must carry current and therefore be
heavy and that the heat generated in the meter is reduced since there is only low current in
the red voltage sense wire to the meter.
An example three-wire hookup is shown in the diagram for reset and transient
voltage protection further on in this document.
Generally, the three-wire connection is the highest performance and is recommended. The
four-wire "jumper cable" approach can be easier to understand and may simplify connector
usage.
Please see our Internet website connection diagrams and FAQ for additional information on
making connections.
"Watt's Up" & "Doc Wattson" Watt Meter and Power Analyzer User's Manual
RC Electronics, Inc.
