EDMI Atlas Mk10, Справочник по аппаратуре

Страница: 30 / 112

2-20
Inputs
The inputs are passive and are isolated from all other circuits, including the other inputs.
There are a variety of input voltages that may be ordered with the meter, e.g. 110V and
240V, down to 5V. Under voltage will cause the input to trigger erratically or not at all,
while over voltage will cause excessive heat dissipation and possible damage to the
meter.
The rated voltage is the voltage that must be applied between the two terminals of the
input. The inputs work with any polarity, and with AC or DC signals. There are a
maximum of 2 inputs for the standard I/O variants (Table 2-1), 4 inputs for the special
I/O variant (Table 2-2), and 3 for the UPS variant (Table 2-4).
Active inputs are also available as a factory option. They use power from the serial port,
and are thus not isolated from the serial port. In this case simply shorting between the
input terminals will cause the input to trigger. The maximum external impedance is 500
ohms. Note that power is drawn from the isolated serial port supply, and the inputs will
not work while the serial port is powered down to cycle power to a modem. They will
continue to operate on a UPS meter when running from the UPS battery.
Outputs
There are several types of outputs available. All outputs are isolated from all other
circuits, including other I/O. See Table 2-1, Table 2-2, and Table 2-4 for details of
isolation and connections.
The SØ outputs are designed to switch up to 24VDC and 24mA.
The relay outputs are rated to 2A, 240VAC with an inductive load, or 5A, 240VAC for
the high current version. These outputs should not be used as pulsing outputs for
transmitting energy pulses, as the output contacts are subject to contact bounce and are
not rated for continuous switching.
The BOSFET outputs are rated up to 240V, 100mA. They may switch either AC or DC
voltages, any polarity.
Battery
The battery is used to run the clock during loss of power. It also allows the meter LCD
to be activated while main power is not available.
The meter comes with an optional internal or external battery.
The external battery is a 3.6V, 700mAh Lithium battery, or a 3.0V, 700mAh Lithium
battery. The Mk10A only supports the 3.0V battery. The internal battery is a 3.0V,
700mAh Lithium battery. If both internal and external batteries are fitted, the meter will
use both.
If an internal battery is used, a jumper will be connected to JP3 pin 1 and pin 2. To use
an external battery, remove the jumper and plug the battery connector to pin 2 and 3
(polarized) of JP3. The external battery is clipped into the compartment to the right of
2-20 EDMI Atlas Hardware Reference Manual