GeoSIG AC-73 Force Balance Accelerometer User Manual
Document Revision
| Version | Date | Modification | Prepared | Checked | Released |
| 1 | 05.12.2012 | First issue | MAE | SER | TAB |
| 2 | 19.12.2012 | Pin out | TAB | MAE | TAB |
| 3 | 20.12.2012 | Minor corrections | MAE | TAB | MAE |
| 4 | 23.09.2013 | Minor corrections | JLT | MAE | MAE |
| 5 | 24.03.2017 | Full scale selection for internal version. Details on test pulse input. New Product Picture | JON | PAT | JON |
| 6 | 08.05.2019 | Spelling and Grammar Corrections | VAG | JOG | VAG |
| 7 | 24.02.2022 | Housing drawing update | KEC | ALB | KEC |
| 8 | 04.08.2022 | Updated Chapter 2, connector types | ALM | ALB | KEC |
Disclaimer
GeoSIG Ltd reserves the right to change the information contained in this document without notice. While the information contained herein is assumed to be accurate, GeoSIG Ltd assumes no responsibility for any errors or omissions.
Copyright Notice
No part of this document may be reproduced without the prior written consent of GeoSIG Ltd. Software described in this document is furnished under a license and may only be used or copied in accordance with the terms of such a license.
Trademark
All brand and product names mentioned are trademarks or registered trademarks of their respective holders.
All rights reserved.
GeoSIG Ltd
Switzerland
Warnings and Safety
The sensor housing provides no protection against explosive atmosphere. It must not be directly operated in area where explosive gases are present.
Basic specifications
| Sensor Series | AC-7x |
| Input range | Acceleration, ±0.5, ±1.0, ±2.0, ±3.0 or ±4.0 g |
| Output range | 0 ± 10 Volt differential output (20 Vpp) |
| Frequency range | DC to 200 Hz |
| Protections | All connector pins are over voltage protected by Transzorb diodes |
| Power supply | 9.5 – 18 VDC |
| Current drain | Average 90 mA @ 15 VDC |
| Test input range | 3-36 VDC |
Electrical Connector
All the AC-7x accelerometers are supplied as standard with a 2 m connection cable. Based on the intended use, the 12-pin metallic-style connectors will be supplied in one of the following options: Binder Serie 623 or Binder Serie 423.
Binder Serie 623
| GeoSIG | P/N #J_CIR.012.002.F |
| Binder Serie 623 | P/N 99 4622 00 12 |
Cable gland nut has to be determined as per cable external diameter and must be separately ordered. It has also to provide the cable shield connection to connector case.
Binder Serie 423
| GeoSIG | P/N #J_CIR.012.010.M |
| Binder Serie 423 | P/N 99 5629 00 12 |
Cable gland nut has to be determined as per cable external diameter and must be separately ordered. It has also to provide the cable shield connection to connector case.
Connector Pin Description
The connector pin assignment and cable colour code can be observed in the table below:
| Binder Connector | SIGNAL | Comment | Colour | ||
| Serie 623 | Serie 423 | ||||
| Pinout | Pinout | ||||
| 1 | A | OUTPUT X (+) | 0 V ± 10 V voltage output, 47 W output impedance | White | |
| 2 | B | OUTPUT X (-) | 0 V ± 10 V voltage output inverted, 47 W output impedance | Brown | |
| 3 | C | OUTPUT Y (+) | 0 V ± 10 V voltage output, 47 W output impedance | Green | |
| 4 | D | OUTPUT Y (-) | 0 V ± 10 V voltage output inverted, 47 W output impedance | Yellow | |
| 5 | E | OUTPUT Z (+) | 0 V ± 10 V voltage output, 47 W output impedance | Grey | |
| 6 | F | OUTPUT Z (-) | 0 V ± 10 V voltage output inverted, 47 W output impedance | Pink | |
| 7 | G | TEST INPUT | Test input, output will result in a sensor step response | Blue | |
| 8 | H | GND | Connected to Recorder’s GND | Red | |
| 9 | J | +12 VDC power | Power input, +9.5 to +18 VDC range, 90 mA @ +15 VDC | Black | |
| 10 | K | 0 VDC power | Power return | Violet | |
| 11 | L | N/C | Reserved | Grey/Pink | |
| 12 | M | N/C | Reserved | Red/Blue | |
Table 1. AC-7x Connector Pin Assignment and Cable Colour Code
Electric Configuration
The full scale is field selectable without gain re-calibration by means of jumpers with fixed 0.1% precise amplifiers.
Mounting
Small size and single bolt attachment allow the AC-7x to be easily installed saving installation time. The integrated bubble level simplifies the levelling done by the three-point levelling screws.
The accelerometers must be firmly mounted to a surface and levelled, as the application requires. Check to be sure that the accelerometer is aligned to produce the desired output signals.
Depending on the measurement setup, the sensor axes should be aligned to the monitored structure (Any main direction of the structure) or to the coordinate plane (North/South, East/West).
Acceleration in the arrow direction indicated on the case will produce a positive output signal.
In case the sensor shall be aligned to the coordinate plane, make sure the surface has a scribed north/south orientation line accurately surveyed from reliable markers. The X-axis of the sensor has to be pointed to East or to any other main direction of the structure to monitor. The Axes can then be interpreted as following:
The accelerometer has a single-bolt fixation. One M8 expanding nut rock anchor must be used for the sensor fixation.
Screw is applied on the mounting surface using the anchor and screw head is left outcropping for 1-2 cm. The sensor then is slotted via the opening under the sensor housing.
Levelling can be done with the help of the bubble level on the housing and the three-point levelling mechanism.
Do not overtighten the three-point levelling mechanism. This may damage the sensor.
Documents / Resources
 | GeoSIG AC-73 Force Balance Accelerometer [pdf] User Manual AC-73 Force Balance Accelerometer, AC-73, Force Balance Accelerometer, Balance Accelerometer, Accelerometer |
 | GeoSIG AC-73 Force Balance Accelerometer [pdf] User Manual AC-73 Force Balance Accelerometer, AC-73, Force Balance Accelerometer, Balance Accelerometer, Accelerometer |
