Coffee Grinder Timer Controller

This coffee grinder timer controller controls the run-time of a grinder. It can be used to control grinders with a simple ON/OFF switch, or with a timer switch. For a grinder with an internal contactor such as the Mazzer with an automatic switch (On/Off + Start),  our model J72MA  should be used. 

The controller has three buttons, which allow the user to activate the grinder for different grinding times.

• Single-shot button
• Double-shot button
• Manual grinding button *

The single-shot button and the double-shot button can be programmed to run the grinder for a specific duration (from 0.01 seconds to 99 minutes). The third button, the manual grinding button, allows the user to manually control the grinder. It will turn on the grinder when it is pressed; turn off the grinder when it is released. The time duration of the manual control is displayed. It can be used for fine-tuning the single or double shot timer setting. All three buttons are momentary buttons. 

(Note *: The manual grinding button can be swapped to a maintained action button upon request. Please contact us for this customization request.)

The controller also has an accumulative timer that accumulates the run time of the grinder until it is reset by the user. The timer unit is programmable. A user can set it to seconds, minutes, or cups. A user can also convert it to weight units (such as grams, ounces, or pounds) with a simple calibration step. It is a useful feature for bookkeeping in a commercial coffee shop.

For a grinder that has a spring-loaded switch or a mechanical timer switch, a user needs to find a way to keep the switch in the ON position. This link provides examples of how to keep the switch at the ON position for Rancilio Rocky and Mazzer with the Time switch. 

Model Option. The original model (J72BX) has all three buttons on the top, which make it easier for the user to operate. In situations where the counter space is limited, the new configuration in J72BX_B, where all three buttons are installed on the front plate, can be stacked with other items on the counter. 

The front view of the J72BX Grinder Timer Box.

The new model J72BX_B with three buttons installed on the front plate.

Power Option. Please select the main power voltage and the output socket if you are located the countries such as the United Kingdom or Australia where a different output socket is required. 

The output socket will accept either a US 120V standard plug (NEMA 5-15P) or a European standard plug (CEE7/7). The output voltage is the same as the input voltage. In other words, if the controller is plugged into a 120 V socket, the output will be 120 V.  If it is plugged into a 240 V socket, the output will be 240 V. The input socket is the standard socket used on computers (IEC320 C14). The controller internal relay is rated 10 A for 120V and 7 A for 240 V (the rating is for resistive load. For the inductive load such as motor, the rating is lower, depending on the inductance).

An input power cord will be included if you select the 120V or 240V version. For the "120V" version, a cord with US plug NEMA 5-15P will be included; for the "240V" version, a cord with a European plug (CEE7/7) will be included. * Please note that for "240V w/ UK output socket", no power cord will be included. For customers from the UK, please find a computer cord locally.

 
The back panel of J72BX for the 120V and 230V version (left) and the Australia 230V version (right).  

Specifications
Timer range: 0.01 sec to 99.99 sec; or 1 sec to 99 min 59 sec.
Power supply: 90 - 260 V AC or DC.
Power Consumption: < 2 W
Relay output: 7 A @ 240 VAC,10 A @ 120 VAC and 24 VDC (resistive load)
Relay life: 100,000 times.
Operating temperature: 0 - 60°C.
Humidity: 0 - 95% RH
Dimension: 120 x 70 x 135 mm, (4.72 x 2.75 x 5.25 inch)
Grinder-activating switch/button: momentary switch, 16 mm cutout hole (SW14). 

Click here for the instruction manual
Click here for application examples
 

Working with Mazzer Mini

Working with Rancilio Rocky

Note
1. Specially modified J72BX with switch dust covers (SDC-16) and/or a maintained action Manual Grinding button is available upon request. See the picture of a demo unit.