CTC Series signal converters turn a compatible current-transformer secondary signal into a two-wire, loop-powered 4–20 mA output for a PLC, panel meter or data-acquisition system. Choose the 0.333 V AC ProteCT input model or the 5 A CT input model. The connected current transformer determines the primary-current scaling, so no field calibration is required.

The converter mounts on standard DIN rail and uses a 24 V DC loop supply (12–30 V DC). Match the converter input to the current-transformer output.

CTC Series Signal Converters — Catalogue CTC Series Signal Converters — Instructions

Select & Configure Model

Base Model #	Power Supply	Output	Input Range	Accuracy	Approvals	Add to Cart / Configure Part #

CTC-333-420-24L-DIN	24 V DC loop-powered (12–30 V)	4–20 mA	0–0.333 V AC ProteCT secondary	1.0% FS	UL Listed - USA & Canada	QTY Add to Cart
CTC-05A-420-24L-DIN	24 V DC loop-powered (12–30 V)	4–20 mA	0–5 A AC CT secondary	1.0% FS	UL Listed - USA & Canada	QTY Add to Cart

Power Supply:

24 V DC loop-powered (12–30 V); Class 2 supply

Output Impedance:

<500 Ω at 24 V DC

Accuracy:

1.0% FS

Frequency Range:

10–100 Hz

Approvals:

UL/cUL; RoHS compliant (instruction sheet)

Overload:

300% FS for 6 seconds

Case:

UL94 V-0 case; 1.44 in W × 4.21 in D × 2.28 in H (36.6 × 106.9 × 57.9 mm)

Output(s):

4–20 mA, proportional to connected CT full-scale primary current

Input:

Model-dependent: 0–0.333 V AC ProteCT secondary or 0–5 A AC CT secondary; primary scaling follows CT ratio

Response Time:

100 ms to 90% of step change

Environmental:

−20 to 50°C; 0–95% RH, non-condensing

Burden:

1.67 VA maximum input burden for stated accuracy

Power Consumption:

2 VA maximum (instruction sheet)

Mounting:

Standard DIN rail or panel mounting

CTC-333-420-24L-DIN accepts a 0–0.333 V AC low-voltage ProteCT current-transformer secondary. CTC-05A-420-24L-DIN accepts a 0–5 A AC current-transformer secondary. Both produce 4–20 mA and use the same 24 V DC loop-powered DIN-rail housing.

These two input types are not interchangeable: do not connect a 5 A CT secondary to the 333 mV converter. De-energize the CT before making connections. A conventional 5 A CT must remain connected to a suitable load whenever its primary is energized.

Use a Class 2 DC supply. The output reaches 20 mA at the rated primary-current limit of the connected CT. See the instructions for wiring and installation.

Compatible sensor families: ProteCT low-voltage current transformers and 5 A secondary current transformers.