AMI 210BR, Руководство пользователя

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AMI Analyzer Manual Installation Procedure
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for Class 1 Div 1 areas. You can use flexible conduit for Class 1 Div. 2 areas. See the NEC
handbook.
All the electrical connections are located in the left hand box – unscrew the cap with the red label. The
picture above shows the AC version (recognized by its black color). The DC version looks the same (except it
is white). The power is brought to the three position unpluggable terminal strip on the left (DC power looks
the same, but it’s marked differently). Make sure the wires are connected per the markings – Hot to H,
Neutral to N, Ground to the ground symbol. For DC units, connect the positive to the “+” symbol, the
negative to the “–“ symbol, and the ground as before. For DC units, the “–“ and the ground are connected
together, but run a separate ground wire to your main ground, and another wire from the – terminal to the
negative terminal on your power supply or battery.
The analog output – which may be either 1-5V or 4-20mA – is connected to the “+” and “-“ symbols. This
signal is isolated from ground. If the device to which you are connecting is also isolated from ground, make
sure you ground the “-“ connection at the analyzer. The terminal marked by the ground symbol may be
used for this purpose, in which case the output is no longer isolated. DO NOT GROUND BOTH ENDS! If you
do so, you will generate a ground loop which will seriously upset the readings. Normally you would use the
ground terminal for a shield. You can select which output is in use. The voltage output is lower power, but
more prone to interference. If you decide to change it, you will probably have to perform an output
calibration, described later in this manual.
The two terminals marked A and B are for the RS-485 ModBus connection. This is not isolated from ground.
There are two alarm contacts. These are two independent switches that either close, or open, their two
terminals. Think of them as being like a single pole light switch. You can determine whether they close
upon an alarm, or open, using the user interface program. They can switch up to 110V at 5A. Good practice
suggests adding snubbing diodes across any load they switch – although diodes are installed already on the
output circuit board. Be careful you don’t use them to short the power supply by attaching one end to your
hot and the other to ground. This can blow traces off the circuit board.
Each relay can be programmed to switch on or off, above or below set point, and with individual time
delays. They can also be set to operate latching valves, so that one contact opens the valve, and the other
closes it. Finally, they can themselves be set to reset automatically, or else to latch in position unless
someone presses the “Alarm hold off” button on the front panel. The User Interface Program must be used
to access all these options.
Run the power and alarm wires through one conduit, and the analog output and RS485 lines through the
other.
Make sure you are following the NEC (National Electrical Code) when you wire it up. In particular, if the
analyzer is in a class 1 Div. 1 area you have to use rigid conduit. You MUST always seal it off, in any case.
Also make sure you have a way of removing power from the analyzer nearby, per the code.
And don’t drill any holes in the enclosure! This will violate the safety approval, and may cause a fire or
explosion resulting in serious injury or loss of life.