10 Diagnostic Tools and Frequently Asked Questions
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Q: Can I extend the CT leads?
A: Yes. You should try to avoid extending the native CT leads by locating the meter next to the circuit
breaker. If you must extend the leads, take into consideration the following inaccuracy contributors. Here
are some of the factors that will affect accuracy when using long CT leads:
1. Wire Length
•
Native CT length is best
•
Longer run decreases accuracy
2. CT wire gauge (18 AWG preferred)
•
Thinner wire > more resistance > affects accuracy
•
Thicker wire > more capacitance > affects accuracy
3. Conduit material
•
Metal conduit will effect accuracy
•
Non-metal conduit has minimal effect
4. High voltage wires run in parallel with CT wires inside the same conduit
•
Approximately 0.7%/100ft. deviation at 277V
•
Approximately 0.5%/100ft. deviation at 120V
•
Accuracy deviation increases as current increases on the voltage wires.
5. Wire type
•
When extending CT leads, twisted pair wire type gives better accuracy.
Q: How do I retrieve Data from the meter?
A: Data Acquisition equipment, also known as Automatic Meter Reading (AMR) and Middleware, consists
of radio transmitters, repeaters, and a collector that monitors, records, and transmits data to energy
management or billing software solutions. Various software solutions manage and display data in user-
friendly formats. See Sections 6 and 7 or go to Leviton.com for more information.
Q: Why are solid core current transformers color coded (Black & white, red & white, and blue &
white)?
A: Industry convention for color coding in 3 Phase 208V electrical systems assigns the color black to phase
A, red to phase B, Blue to phase C, and white to Neutral. Leviton‘s 100A and 200A solid core CTs are coded
with the same colors (on the body of the CTs and on the wires) to help installers get each CT placed on the
correct hot leg. Further, the white half of the CT always faces incoming Line or source. Phase A CT (black)
connects to CT1 at the meter, phase B CT (Red) connects to CT2, and phase C CT (blue) connects to CT3.
See hookup diagrams in figures 8 and 9.
Q: Can digital output wires be routed through the same conduit as voltage input and current
sensing wires?
A: No. In accordance with NEC and UL requirements, Class 2 wiring (digital inputs/outputs) must be
separated from Class 1 wiring. Digital output wires must enter the meter housing through the top of the
enclosure, and voltage and CT wires must enter at bottom of enclosure. See Installation Instructions
in Section 3.
Q: I still can’t get my meter to work, what now?
A: Contact technical support at via phone or email; see Contact Information on following page.
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