• Capture energy information for up to 4 circuits.
  • Simple and convenient way to connect up to 4 CTs to the WebMeter36F™.
  • Ideal for connecting single and multiple phases or remote pieces of equipment to the WebMeter36F™.
  • Use up to four JBox-8s with one WebMeter36F™ and/or combine them with JBox-4s.


Current transformer wiring that originates from a breaker panel is considered a Class 1 circuit by both the National Electrical Code (NEC) and the Canadian Electrical Code (CEC).

JBoxes provide a convenient way to isolate CT wiring from class 2 devices such as CircuitMeter’s WebMeter36F™ product. Corrections to phase error and gain errors are performed by the WebMeter36F™.

This enables a flexible installation process utilizing standard CAT5 cables. The JBox-4 is a 4 port configuration allowing a single JBox-4 to connect up to 4 CTs to a WebMeter36F™.

Use any combination of JBox-4’s and JBox-8’s to connect a total of up to 36 CTs to a WebMeter36F™. Use standard Cat5e cable for to connect the JBox-4 to the WebMeter36F™.

Supported Current Transformers from CircuitMeter

Solid Core All current transformers offered by CircuitMeter (up to 6000A)
Split Core All current transformers offered by CircuitMeter (up to 6000A)

Device Specifications

Isolation Input to Output 2.5 KV (hi-pot test)
Frequency 50/60 Hz


Supports 4 CT
Connector Type Spring Cage
CT Current 20 mA


RJ45 (T-568B) 1
CT Current 10 mA

Mechanical & Dimensions

Weight 640 g (1.41 lbs)
Size 12.192 cm / 4.80 in (W)
12.192 cm / 4.80 in (H)
5.080 cm / 2.00 in (D)

Safety Certifications

Safety Standards¹ UL 610010-1
CAN/CSA C22.2 No. 61010-1


Operating Temperature 0ºC to +70ºC
Storage Temperature -17ºC to +80ºC
Humidity 10 to 90% non-condensing
Enclosure Metal


¹ Safety Standards Pending Approval
** Subject to Change Without Notice **

Additional information