811A / 812A Intelligent Alarm, DC Voltage / Current Input by Acromag

Companies & Organizations:

United States of America

Acromag, Incorporated
30765 South Wixom Road
Wixom, Michigan 48393-2417 USA

- ±100V or 0 to 22mA DC input ranges or 2 input channels, ±100V or 0 to 22mA DC input ranges (AC current with optional sensor)

- Single or dual mechanical relays

- 10-36V DC power

- Software configured; multi-function alarms (limit, window, deviation, rate-of-change, peak/valley detection); on/off controller capability


IntelliPack alarms compare inputs against userdefined limit setpoints to control built-in relays.


Each unit offers a selection of input ranges and alarm functions to handle a broad range of applications. As your needs change, you can easily reconfigure the unit for different ranges or functions. Alarm functions available on all models include on/off controller, limit alarm, window alarm, deviation alarm, rate-of-change alarm, and peak/valley detection.


Setup is very easy. IntelliPack alarms are configured through a user-friendly Windows XP/Vista/7 program. Field adjustments and recalibration are quickly performed with front-panel push-buttons and status LEDs. Once configured, IntelliPacks operate independent of any host computer.



General Input


Analog to Digital (A/D) Converter: 16-bit S-D A/D converter.

Ambient Temperature Effect: Better than ±0.005% of input span per °C or ±1μV, whichever is greater.

Noise Rejection

Normal Mode: Better than 40dB @ 60Hz.

Common Mode: Better than 100dB @ 60Hz.

Input Filter: Normal mode filtering, plus digital filtering optimized and fixed per input range within S-D ADC.

Input Response Time: Less than 100mS to 98% of final value for a step change in the input. A software programmable delay can be implemented for filtering transients.

Relay Time Delay: Adjustable alarm delay of up to 25 seconds.

Input Overvoltage Protection: Bipolar Transient Voltage Suppressors (TVS).

Accuracy (DC Voltage/Current Inputs): Better than ±0.05% of input span.


DC Current Input


DC Current Input Range

Input Ranges                        Resolution

0 to 5mA DC                         189nA/LSB

0 to 22mA DC                       757nA/LSB


DC Current Input Impedance: 24.9 ohms.

Excitation Supply (for 2-wire instruments): +15V DC, 24mA maximum.




DC voltage Input


DC Voltage Input Ranges

Input Ranges            Resolution

±100V DC                3.77mV

±50V DC                  1.88mV

±25V DC                  942μV

±12V DC                  471μV

±6V DC                    236μV

±3V DC                    118μV

Input impedance: Greater than 500K ohms.


AC Current Input


AC Current Input Range (optional): An optional external AC current sensor is required to monitor AC current signals (Model 5020-350).

AC Current Range    Primary Turns

0 to 20A AC               1

0 to 10A AC               2

0 to 5A AC                 4

0 to 2A AC                 10

0 to 1A AC                 20




Relay (811A-0100 model): One DPDT electro-mechanical relay. Contact material Silver Nickel (AgNi 90/10).

Relays (811A-0200, 812A-0200 models): Two independent SPDT electro-mechanical relays. Contact material Silver-Cadmium Oxide (AgCdO).

Relay Ratings (CSA ratings): 25V DC @ 5A. 120/240V AC @ 5A.

Expected Mechanical Life: 20 million operations.




Ambient Temperature

Operating: -25 to 70°C (-13 to 158°F).

Storage: -40 to 85°C (-40 to 185°F).

Relative Humidity: 5 to 95%.

Power Requirements

811A: 10 to 36V DC. 70mA @ 24V. 110mA @ 15V.

812A: 10 to 36V DC. 110mA @ 24V. 155mA @ 15V.

Isolation: 3-way (input/output/power). 1500V AC for 60 seconds or 250V AC continuous. Inputs share a common on 812A Model.

Radiated Field Immunity (RFI): EN61000-4-3, EN50082-1.

Electromagnetic Field Immunity (EMI): No relay trips will occur beyond ±0.25% of input span from setpoint under the influence of electromagnetic fields from switching solenoids, commutator motors, and drill motors.

Electrical Fast Transient (EFT): EN61000-4-4, EN50082-1.

Surge Withstanding Capability (SWC): EN61000-4-5, EN50082-1.

Electrostatic Discharge (ESD): EN61000-4-2, EN50082-1.

Radiated Emissions: EN50081-1 for Class B equipment.

Approvals: UL, cUL listed (USA, Canada). UL3121 - general product safety.




Software Configuration: Units are fully programmable via the Windows XP/Vista/7 IntelliPack Configuration Program. Configuration downloads from PC through EIA232 serial port using Acromag 800C-SIP kit.

Field Configuration: Setpoint and deadband are configurable via push-buttons and a standard calibrator.

LED Indicators: LEDs indicate power, status, and alarm.




Enclosure Case: Self-extinguishing NYLON type 6.6 polyamide thermoplastic UL94 V-2, color beige; general purpose NEMA Type 1 enclosure.

Connectors (Removable terminal blocks) Wire Range: AWG #14-22 (AWG #12 stranded only).

Printed Circuit Boards: Military grade FR-4 epoxy glass circuit board.

Dimensions: 1.05W x 4.68H x 4.35D inches. 26.7W x 118.9H x 110.5D millimeters.

Shipping Weight: 1 pound (0.45 Kg) packed.




Features & Benefits


Integrated microcontroller performs intelligent signal processing for advanced alarm functions.

Windows XP/Vista/7 software configuration speeds setup and replacement.

Push-button reprogrammability facilitates changes in the field without a host PC.

Multi-purpose inputs accept numerous ranges to reduce spare stock requirements.

High-resolution Sigma-Delta A/D converter delivers high accuracy with low noise.

Input excitation supply on each input provides power for a two-wire transmitter.

Dual alarm operation lets you perform two alarm functions at the same time.

Defense Products & Services: 811A / 812A Intelligent Alarm, DC Voltage / Current Input by Acromag
Companies & Organizations: 
Defense Products & Services Sectors: Computers components
Description: 811A / 812A Intelligent Alarm, DC Voltage / Current Input
Source of Information: Acromag Inc