DROK 4-20mA Generator, Adjustable Signal Generator, DC 0-10V 0 4-20mA Current Voltage Analog Simulator for Value Adjusting PLC Panel LED Testing

I may HVAC technician and I purchases to help troubleshoot damper motors on equipment economizers

This is a nice tool, and inexpensive. It can be powered by a 24VDC power supply, or I used 2 9V batteries in series. There is one terminal for V-Out, one for I-Out, and one for A- Com. If you do not know what any of these terms mean, this is not the device for you.There are capabilities to edit patameter set for both current and voltage. Another reviewer posted snip of settings and procedure. I used these to get I-Out from a 4-20mA down to a 0-20mA output.Relatively small device, great for portability. Approximately 4" x 2" x 2"I will probably locate a hard case and line it with foam pad to store device.

I was ready to chuck this gizmo into the trash and write a one-star review, because I thought it was useless, at first.My mistake was in believing the label that said 12-24 volts. I had connected a beefy 12 volt supply (actually a little over 14 volts). This device didn't work well at all on a nominal 12 volts.But before giving up, I wired two 9 volt batteries together and gave it an 18 volt supply. Whoa, that's the ticket. With an 18 volt supply, it does what I wanted. I'm not looking for super accuracy with a $30 gadget. But I wanted to be able to put out a variable current so I can test some equipment before it's fully on-line. This unit does that well, as long as you provide enough juice. The display isn't perfectly accurate, but you can monitor this with a VoltOhmMeter. I didn't have much success with the calibration pots on the back side of the board, but it works reasonably well if you can live with it.There is no manual with this, so you better know what you want. I connected the 18 volt battery to 2 terminals. Another terminal is common, and there are 2 more terminals. One of these provides a constant voltage, up to a little above 10 volts (relative to the common terminal.) The other terminal provides a constant current up to about 20 mA, relative to the common terminal.The knob will rotate 4 turns, and it varies the current or voltage from minimum to maximum. What isn't obvious is that the tiny switch is changing the DISPLAY from volts to mA. Only the display. The knob changes the output on both the volt and the milliamp terminals simultaneously, regardless of the switch position. Duh, why wasn't that obvious to me?So it's a surprisingly worth while little tool. I wouldn't use this on a mission to Mars, but for general troubleshooting and testing, it's worth the price and then some.

I needed to prove something at work. I had a rudimentary PLC that sends a 4 to 40ma signal. It used a potentiometer to measure fuel level, and the 4 to 20ma signal output is proportional to that input. I had an unused Analog input on a Caterpillar 4.2 panel. The panel used a 0 to 5Vdc input. Using a 250 ohm resistor, I was able to obtain a volt drop across the resistor in the 1 to 5Vdv range. Using this signal generator, I was able to emulate the PLC's output signal and program a CAT 4.2 panel to read fuel level with a 4 to 20ma signal. I had to prove it on our shop's gen before we could suggest it as an upgrade to any customer's gensets.The device is not accurate when it is shipped. BUT its has trim pots on the backside. These are just to make the display screen read the same as the output. I have not really messed with them, as inacurate display readouts were not something I needed to worry about because I was watching with my Fluke 87V.My needs were satisfied, the output is adjustable, and the price was excellent. If I dabbled more in the world of automation, then I might need something more. But then again, maybe not.

I received the apparently updated SG-03S not the SG-02 shown in the photos. I was immediately disappointed at the lack of physical calibration described. After digging, I found I file that will allow you to access the menus to configure the device. The device has a clicky knob, but I had to pull the knob off in order to click it down. It has a distinct tactile click to it. Ones I was able to very these instructions did work I began modifying mine for battery power. Drok really should include these sheet of paper with each unit or make it clear where to find on the product website. They should also update the Amazon listing so people can use this properly! Without these instructions I don't think anyone would be able to figure out how to access the menus.

This is a pretty good device and it gets the job done. I used it to test 4-20 mA current loop readers. It could be better, and it's missing a few features other similarly-priced products have. If you want more features, operating instructions, or guidance on how to use the product, you may want to keep shopping.It needs external power. I used 24VDC connected to the 24V and 0V(GND) terminals. I'm measuring current (example 4-20mA current loop) so I connected my input device to the ACOM(-) and IOUT+ terminals. FYI, research suggests 0V(GND) and ACOM are sharing the same ground. When switching the display from V (voltage) to A (current), the output begins at 4.00 mA. Turning the dial increments/decrements in units of 0.1mA, and tops out at 20.0mA. I may need to research further, but the unit doesn't appear to allow output below 4.00mA or above 20.0mA, which can be useful to test under and over-current detection.Features I'd like to see:1. self-powered, perhaps by USB-charged battery2. output variable beyond the typical 4-20mA limits3. with connection to a 4-20mA output source, a means to READ and display the mA value detected.

Excelente generador, me gusta más el completamente análogo porque me ha llegado dos versiones ( un generador digital y uno análogo). El el generador digital se notan los brincos de corriente o voltaje ( en valores muy bajos) pero es más seguro porque cada ves que pierde la alimentación de la fuente pasa a 0VDC o 0mA. El análogo es estable en su señal y se siente de excelente tacto y respuesta.