This safety ohmmeter / megohmmeter was developed to carry continuity and isolation measurements on pyrotechnical elements where user safety is at stake.
Two types of conditions define the user safety:
Measurement conditions:
Measuring current much lower than the current of non-fireConnection to the test line only for the activated period of measurementDischarge of residual electrical charges
Safety conditions:
No overshoot of maximum current even in case of instrument failure (electronics breakdown, internal short-circuit…)Permanent self-checking of the instrument internal functions before connection to measurement channelMeasurement principle
The ohmmeter function is based on 4 wire measurement, which makes it possible to be freed from parasitic line resistance. The principle relies on an internal device of permanent self-calibration which guarantees, over a short and long-term period of time, the high reliability of the measurements carried out by continuously correcting the drifts of gain and offset.
Measurements start with an external input signal. The result of the measurement is internally processed to supply information whether the measured value is within tolerance limits set by the operator.
All parameter settings are entered by keyboard with a locking of the parameters by key. Our units are equipped with dry contact output and S232 connection that allows process automation and implementation of traceability.
On request, our existing products can be adapted to your specific requirements: Adapted protocole RS232, other testing voltage or measuring current, integration, processing software...
Two switching units (INT 17 and INT 17 HT for high testing voltage) are also available in option to interface the devices under test (initiators, airbags…) with IND pyrotechnical ohmmeters / megohmmeters. The contact switches are usually monitored by shared automation (0 24 V) and earth bounding control (contact or transistor). Automation inputs are protected against any change of polarity.
Large applications:Automotive airbag inflator / electrical module functional testsSeatbelt pre-tensioner actuator / electrical module functional testsHigh speed parallel soak dual inflator or dual test station electrical seekMulticontact / switch dry circuit continuity and leakage resistance measurementsAutomotive power / fuse center continuity and leakage characterizationPCB / PWB and general purpose short/open circuits testingTechnical support:Our technical staff can support you:Commissioning of your equipmentManagement of units evolution (number and functional needs)On site breakdown servicingUnit integration on test benchOn site investigation of any measurement issues Yearly calibration is highly recommended in order to control the safety functions of your equipment.
