Electric CENTRIC Vector Mapping Scan
₹6.50 Square Foot
Electric CENTRIC Vector Mapping helps the user to do the Quality Assurance and Troubleshooting of applied waterproofing membranes and coatings by following the principal of Vector Mapping. The testing procedure has been described as Electric Field Vector Mapping (EFVM) under ASTM D7877 : Standard Guide for Electronic Methods for Detecting and Locating Leaks in Waterproof Membranes.
It’s a low voltage, non-‐destructive testing technology which takes minimum set up and helps user to identify breaches as small as pin-‐hole with electric accuracy. It makes ‘Flood Testing’ look barbaric and outdated way of doing QA.
- Waterproofing membrane (baring few exceptions) act ikel an isolator of electricity.
- First step is to ensure that waterproofing layer is installed directly on a ‘conductive’ substrate. Inverted deck, Concrete RCC slab etc. are inherently conductive and needs no special caution.
- Conductive Sensor Wire is installed on the topside of waterproofing layer on periphery (approx. 200 Sq.M. zones)
- Pulse Generator (Low Voltage) is used to directly feed Positive Charge in the Substrate underneath the waterproofing AND direct ‘Negative’ pulse in to Conductive Sensor Wire
- Waterproofing layer by itself acts like aseparation layer creating potential difference by not letting ‘Negative’ pulse on the topside meet ‘Positive’ ground underneath the membrane.
- Technician has to walk the surface of a wet membrane using Centre Zero Display Scale comparing pulse amplitudes fed thereto through Two Reading Probes in hand
- The largest pulse amplitude is displayed as acentre zero indication on a Centre Zero Display Scale. As a result of the zero centre indication of the display scale instrument, the pulse amplitudes which increase in the direction towards the leak location are indicated by the pointer/ vector of the instrument,
- Just by following the direction of a pointer, technician is able toprecisely locate a ‘leak’!
Ideal for ‘Exposed’ flat roof (Horizontal) waterproofed surfaces. Quality Assurance using Electric Centric Scan is beyond comparison to age old ‘Flood Testing’ method which has several limitations as known by industry.
Perform leak testing by an Electric CENTRIC Vector Mapping Scan .The testing procedure has been described as Electric Field Vector Mapping (EFVM) under ASTM D7877 : Standard Guide for Electronic Methods for Detecting and Locating Leaks in Waterproof Membranes administered by a certified technician as follows:
- Test the entire roofing membrane on an area-by-area basis as required by the conduct of the Work. Install stationary impulses conductor wire around perimeter of area. Provide conductor wire consisting of braided polyethylene (1.5 mm diameter) interwoven with a minimum of nine strands of stainless steel wire.
- Place conductor wire 150mm from perimeter and secure against accidental movement or damage. Place wire directly on membrane. Isolate metal items contacting the membrane by placing four to six additional stands of conductor wire to isolate the field or by removing the metal items temporarily if possible. Bring connection wires to an agreed upon location and place within watertight conduit and indentified watertight junction box so as to allow for future testing.
- Wet the membrane test area with water or other suitable conductor fluid prior to start of each test and maintain wet for duration of testing. Utilizing a potentiometer and two probes placed at the surface of the membrane detect the presence or absence of electrical flow across the surface of the membrane. Verify integrity of the membrane at drains and penetrations by localized testing. Such water electronic testing may be conducted on an area by area basis as the Work permits but in no case shall less than 100% of the roof membrane be tested. If leaks occur, remove existing components and replace with the new material to eliminate the causes and sources of the leaks.
- Record each day’s test result with a written description and photograph of defects and corrections made and a schematic CAD drawing indicating location of stationary conductor wire and of defects found in testing to within 50mm of accuracy.
- The client will remain responsible for all non-refundable travel expenses including lodging & boarding incurred if, for any reason, the scheduled testing date is changed or cancelled by the client.
- On the day of the scheduled Electric CENTRIC Vector Mapping Scan, the client is to provide:
- Water access with proper water pressure (One Tap point on each floor where testing is requested)
- A 110 volt power supply that is capable of delivering a three-pronged grounded service within 100 m of testing location. (One tap point on each floor where testing is requested)
- Safe access to all test areas, prior to the technician arriving to the site. This includes all ladders and access forms being in a safe and working condition, at the correct height if the technician has to use ladder access, and all ladders must be properly tied off and secured prior to and during the technician’s arrival.
- Drains within the test area must be cut-out, free-flowing, and the tie-down pipes are properly connected.
- Test area is to be cleared of materials, debris and construction wastes to allow for safe access and un-obstructive testing.
- To facilitate future testing of a roof, the exposed metal projections (i.e., anchors, metal stacks) must be wrapped with membrane or membrane materials compatible with the membrane to stop the flow of electricity through the overburden and making a connection to the metal.