CRUISING ELECTRONICS E-Meter, Руководство пользователя

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Special versions of Your Meter are available, for additional charge, which
include a solid state Alarm Switch to ground via rear panel terminal strip
Pin #7. This option is use in a variety of settings such as lift pump lock
out on fork lifts, two wire generator start/stop, audible low battery alarms,
and charge controllers. The additional circuitry of the switch may not be
retrofitted to Your Meter in the field. It must be included at the time of
manufacture.
The Low Battery Alarm Switch goes low to meter ground when the alarm
is activated. In other words, a sinking FET switch to the meter's negative
power lead is completed while the alarm is active. This lead is protected
against polarity reversal so the "switch" connection has about 1 Ohm of
resistance. This should be taken into account when sizing relays or de-
signing logic interfaces. The maximum amount of current which may be
controlled by this circuit is 150 mA (0.150A) at no more than 50V. Below
are two typical applications for the optional Low Battery Alarm Switch:
+ DC Alarm Power.
Negative must be common
to Your Meter.
12 V or 24 V
Piezo alarm
<150 mA.
Optional Alarm Switch
AUDIBLE ALARM RELAY DRIVER DIAGRAM
>
RELAY COIL
To Pin 7, Your Meter
rear panel term. strip.
Controlled Circuit
1234
1234
1234
1234
1234
1234
1234
1234
1234
1234
1234
1234
1234
1234
To Pin #7
Your Meter
12
12
Alarm Defeat
Switch On-Off
+ DC Relay Power (<50V). Nega-
tive must be common to Your Meter.
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