King Electric SCM - Manual (Page 13)

13
SAVE THESE INSTRUCTIONS
INSTALLATION — CONCRETE
Concrete Application continued
Step 3: Use a digital multi-meter to measure the resistance between the conductors of the cable/mat power leads again. Record these re-
sistances in the SC Cable / SCM Mat Testing Log under the section “Test Record # 2 After Installation”.
Step 4: Feed the power leads through the conduit into the junction box, leaving at least 6 inches of free lead length. Securing the heating cable
and splice so that they will not be pulled into conduit.
Insert a generous amount of electrical conduit sealant into the conduit end around the power leads to prevent water entry.
Step 5: If a slab sensor is being installed, place the sensor socket according to the instructions. Secure and seal it to the conduit installed earli-
er. It should be located halfway between heating cables and in an area recommended by the sensor manufacturer. Make sure the top of the
sensor will be flush with the surface of the finish layer. Make sure it is protected with a cap or seal.
Step 6: Take a photo of the cable/mat installation. This can be very helpful later for utility work, changes to the site, etc to avoid possible
damage. Keep the photos with this installation manual.
Step 7: Before beginning work, inspect the cable/mat for damage and secure any cable/mat that may have come loose.
To avoid burying any possible damage that may have occurred since the mat was laid, the following tests should be performed:
Use a digital multi-meter to measure the resistance between the conductors of the cable/mat power leads again. If possible, your electrician
should perform an insulation resistance test on the cable/mat. A mega ohm meter adjusted to a minimum 1000 VDC should give a measured
value at least 20 mega ohm (MΩ).
Important
Be prepared to install a marker plate or other identification indicating the presence
of SC/SCM in the slab. This helps alert and avoid possible damage from future on-
site. Install a marker plate where clearly visible in each snow-melted area. A mark-
er plate is placed flush in the wet concrete surface or soft asphalt surface. Other
types of surfaces should be made to allow the marker plate to be installed flush
with the surface. Do not damage the heating cable.
Step 8: Pour concrete over the base and SC/SCM cable/mat so that no less than 1-
1/2” and no more than 3” covers the top of the heating cables. The slab should be
a minimum of 4” thick total. Driveways normally require thicker. Follow building
code requirements for required thickness.
Important
Do not use sharp tools which could damage the SC/SCM. Blunted shovels should allow you to work the concrete carefully into all areas.
Make sure the heating cable is fully embedded, as well as 2 to 6 inches of the conduits enclosing the power lead and slab sensor wiring (if
used). Allow the concrete to fully cure as required by the concrete supplier. Do not energize the SC/SCM cable/mat except to briefly test it, as
this would improperly accelerate the curing and potentially cause concrete damage.
Step 9: Use a digital multi-meter to measure the resistance between the conductors of the cable/mat power leads again. Record these re-
sistance in SC Cable / SCM Mat Testing Log under the section “Test Record # 3 After Covering is Applied”.
DO NOT energize the SC/SCM system until the asphalt is fully cooled and cured per the manufacturer.
KING ELECTRIC MFG CO · 9131 10TH AVENUE SOUTH · SEATTLE, WA 98108 · PH:206 762 0400 · FAX: 206 763 7738 · www.king-electric.com