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PLEASE NOTE: The JR-1, JR-2, and CI-30 will no longer be manufactured once stock is depleted. The successor to these units is the TH100A Current Interrupter.

All M. C. Miller Current Interrupters include a Calibration Certificate

  • Mercury relay: 100 Amps max. switching @ 48VDC or @ 120VAC
  • User Selectable input voltages (100 VAC, 120 VAC, 230 VAC and 240 VAC)
  • Crystal controlled timing
  • Rechargeable battery
  • Immediate or delayed interruption operation
  • Low battery indicator
  • Can be clock synchronized with other JR-2 units or with JR-1 units
  • Synchronization better than 1 millisecond
  • Synchronized operation with any number of JR-1's and JR-2's

Custom LCD, wide operating temperature range, -20°C to +85°C (-4°F to +185°F) with enhanced response time at extremely low temperatures. Large(.7" high) digits plus equipment status annunciators.

CMOS Microprocessor, 8-bit; EPROM operating system. EEPROM, initializes prior setting on power up.

Sealed, Tactile feedback; 4x4 Matrix; "0-9"; "?"; "ENTER"; "CLOCK SET"; "START SET"; "ON CYCLE"; "OFF CYCLE" Keys.

Cycle Range:
Keyboard Programmable: .1 to 999.9 seconds in .1 second increments either "ON" or "OFF" cycle.

Auto Turn-on:
Present interrupt start time, eg. 0700

Night Latch:
The JR-2 supports 24-hour timing and a scheduled relay closure period. For example, a night latch time of 1700 could be entered from the keypad, and a start time of 0700. The unit will operate normally until 1700, at which time the relay will close and will stay latched until 0700 the next morning, then the normal interrupt cycle will begin again. This feature facilitates full CP polarization during hours when the survey crews are absent.

Timing: 0.5 second maximum variation in 24 hours. Synchronization to within 1 millisecond.

Relay Start Position: Is in closed position.

Mercury Plunger type:

100 A @ 48 VDC 100 A @ 120 VAC
75 A @ 75 VDC 90 A @ 240 VAC
50 A @ 120 VDC 60 A @ 480 VAC
30 A @ 240 VDC 40 A @ 600 VAC

Sealed, rechargeable, 12 Volt, 6 A/H Charging plug included.

Battery Life:
Use dependant, example:
1 second off - 4 seconds on = 50 hours
4 seconds off - 1 second on = 15 hours

10" H x 10.75” W x 5” D, (26 x 28 x 13 cm)

13 lbs. approx.