CTSERIES ATC | Alldatasheet

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Technical content

Diversified Electronics 800.727.5646 atcdiversified.com DIMENSIONS (MM) CT-500/5, 1000/5 SPECIFICATIONS INPUT/OUTPUT Rated primary rating 30A to 1000A Rated secondary output 5A TECHNICAL Rated burden (VA) 1VA to 15VA SPECIFICATIONS Class of accuracy 0.5 to 5 Thermal Nominal Continuous 120% of In Rated Current (Icth) Thermal short circuit current (Ith) Ith = 60 X In for 1 sec Instrument security factor FS <5 Insulation class E (120°C max) Max operating voltage (Um) 720V maximum Isolation test voltage 3kV AC 1 min Nominal rated frequency AC 50Hz - 60Hz ENVIRONMENTAL Ambient temperature 0°C to +50°C SPECIFICATIONS Humidity < 95% RH (non-condensing) Storage temperature -5°C to +50°C MOUNTING Mounting modes Panel Mount / DIN Rail Mount STANDARD Applicable standard IEC 61869-2 CURRENT TRANSFORMERS Diversified Electronics 800.727.5646 atcdiversified.com CT Series Current Transformers The CT Current Transformers are available in a wide range of bus bar sizes and a current measuring range of 30A to 1000A. The transformers are CE and UL cURus listed.

  • Use with different bus bar
  • Accuracy: Class 0.5 to 5
  • 30/5 to 1000/5 Amperes
  • Panel Mount/ DIN Rail Mount (Optional Accessory)

ORDERING INFORMATION

MODEL CURRENT RATIO BURDEN ACCURACY CLASS CT-30/5 30/5 A 1 VA 5 CT-50/5 50/5 A 1.5 VA 3 CT-100/5 100/5 A 3 VA 1 CT-200/5 200/5 A 2.5 VA 0.5 CT-500/5 500/5 A 5 VA 1 CT-1000/5 1000/5 A 15 VA 0.5 ACCESSORIES DIN Rail Clamp CTDRC CTDRC - DIN Rail Clamp IND. CONT . EQ. 496Y

Example: 1. Measure the current on each leg. Assume A = 10 amps B = 12 amps C = 9 amps 2. Find Average 10 + 12 + 9 = 31 = 10.33 3 I max = 12 I avg = 10.33 3. Apply formula 12 - 10.33 = 1.67 1.67 = .139 x 100 = 13.9% unbalance 12 CURRENT MONITORS THREE PHASE CURRENT UNBALANCE EXTERNAL CURRENT TRANSFORMERS Balanced or matched currents on a three phase system are difficult to maintain because of the many varying factors involved such as, unequal single phase loading, poor connections and cabling and/or dirty or burnt starter contacts. Although these varying factors can be controlled to maintain as close as possible a balanced line, the unseen conditions such as overheated motor windings, burnt bearings, low voltage, high voltage and single phasing need to be constantly monitored to protect your valuable equipment. The CLB Series Three Phase Current Unbalance and Over Current Monitor (page 176) offers this protection. To determine the condition of your three phase line and to properly select the CLB Series percent unbalance setting a simple calculation formula is needed as follows: (I max - I avg) x 100 I max The load or burden that can be connected to the secondary of the Current Transformer is usually specified in VA. The rated accuracy of the Current Transformer is guaranteed only when the sum of the VA ratings of all devices (ampmeters, wattmeters, current monitors, etc.) connected to the secondary windings does not exceed the specified VA rating. The interconnecting conductor resistance must also be considered, especially when the Transformer is installed at some distance from the Current Monitor or other load. For the wiring, the VA can be calculated using Ohm’s Law: VA = E x I = (I x R) x I = I2R Where I = 5 Amps and R is the DC resistance of the wire. All of the standard DE Current Transformers have a rating of 2 VA except the 2500/5 version which has a 5 VA rating. From the above formula we can also calculate the maximum resistance that can be connected to the secondary of a Current Transformer: VA=I2R, Hence R = VA Example: VA = 2 Rmax = VA = 2 = 0.08 Ohms = 80 milliohms I2 (5)2 VA = 5 Rmax = VA = 5 = 0.2 Ohms = 200 milliohms I2 (5)2 If the only load on the Current Transformer is a DE Current Monitor, its VA rating (approx. 0.15 VA) is small compared to the Current Transformer rating and can be neglected. This means that the resis- tance of the wiring can be 80 milliohms max. for the 2 VA units and 200 milliohms max for the 5 V A unit. Gauge Ohms per 1000' Milliohms per foot AWG 14 2.5 2.5 AWG 16 4.0 4.0 AWG 18 6.4 6.4 AWG 20 10.0 10.0 Example: For a 2 VA Current Transformer, the length of AWG 16 wire would be: 80 milliohms 4.0 milliohms/ft = 20' Because we are dealing with a pair of wires, the maximum distance from the Current Transformer to the Current Monitor can be only 10 ft. As we can see, it is important to keep the wire length to minimum, use heavy wire, and keep all connections clean and tight. CT Series