AddMe III contains no configuration jumpers. There is no need to open the enclosure. Analog input types are switched between voltage and thermistor inputs under software control.

I/O points should be connected as indicated in the various diagrams below. In addition to selecting a wiring diagram, the corresponding selections should be made in the configuration registers accessible from the configuration tool to inform software of your intentions.

I/O Point Type
Wiring Guide
 Additional Information
A/UI Analog Input:
0-10VDC
Voltage Input
AI inputs 1-18 will accept voltage inputs of up to 10VDC. Voltages to 12VDC will be measured. Voltages to 24VDC will be tolerated, but measurement is internally limited to a reading of 12VDC.
A/UI Analog Input:
0-20mA
Current Input
AI inputs 1-18 will accept current inputs of 0-20mA with the addition of a 500 ohm 1/2 watt external resistor. A 500 ohm resistor will produce a 0-10VDC signal. A 250 ohm resistor may also be used to produce a 0-5VDC signal.
A/UI Analog Input:
Thermistor Input
A/UI inputs 1-16 will accept thermistors of 3k, 10k, or 20k ohms. Linearization via interpolation of a 56-point table is performed internally.
A/UI Discrete Input:
Discrete Voltage
A/UI inputs 1-16 may be connected as discrete voltage sensing inputs. Inputs up to 24VDC are tolerated, but threshold sensing only functions over the 0-10VDC range.
A/UI Discrete Input:
Dry Contact Closure to Ground
A/UI inputs 1-16 may be connected as discrete inputs sensing dry contact closure to ground. Internal excitation of 5V @ 1mA is provided.

Recommended software settings: Dry Contact, Inverted, Threshold = 50%.

Voltage present will generate a binary 1. A closure to ground will force voltage to zero. Therefore, "inverted" will generate a binary 1 when the contact is closed resulting in zero volts present at the input.

P/DI Discrete Input:
Discrete Voltage
P/DI inputs 1-2 may be connected directly to a DC voltage up to 24VDC for discrete sensing.
P/DI Pulse Input:
Frequency or Total Count Input
P/DI inputs 1-2 will measure frequency up to 5kHz or count pulses in total count mode. Inputs may be TTL to 24VDC. Counts are stored to non-volatile memory every 15 minutes, and restored upon power-up. Non-volatile count is stored as a 32-bit floating point number.
Analog Output:
0-20mA Current Output
AO outputs 1-4 produce outputs of 0-20mA. Use of an external 500 ohm resistor will produce a 0-10VDC voltage output. For best results, locate the resistor at the input of the receiving device.
Discrete Output:
Form A Relay
AC Load
DO outputs 1-8 are Form A dry contact relays rated for 5A @ 120VAC (resistive). Snubbers should be used with inductive loads.
Discrete Output:
Form A Relay
DC Load
DO outputs 1-8 are Form A dry contact relays, also rated for 5A @ 30VDC (resistive). Snubbers should be used with inductive loads.
Power
Connect AC or +DC power to Power terminal. Connect common or -DC power to GND terminal. GND is common to all terminals labeled COM.
Power consumption is 7.5 watts, or 0.3A @ 24VDC.
Communications
Connect RS-485 network to NET+/- terminals.
Communication signals comply with EIA-485 standard.
Wiring Terminals
Screw terminals ratings are substantially in excess of any I/O point ratings.

Screw terminals are pluggable. They unplug from the unit in 13-position blocks. Any combination of smaller 5.00mm terminal blocks can optionally be used instead.