Q 6.1 0 Td <70> Tj ET 6 0 Td <20> Tj 4.3 0 Td <20> Tj 6.1 0 Td <6976> Tj ET 3.1 0 Td <6F> Tj 4.2 0 Td <79> Tj 3.1 0 Td <74> Tj 6.7 0 Td <75> Tj 5.3 0 Td <61> Tj 6.1 0 Td <72> Tj 6.2 0 Td <696E> Tj 6 0 Td <63> Tj 4 0 Td <64> Tj This measures the voltage and current at the same time, and even calculates the mAh for you. 6.1 0 Td <20> Tj 6.1 0 Td <65> Tj 4.1 0 Td <74> Tj 5.5 0 Td <74> Tj Conventional mosfets can be used but you would be limiting the range of voltages/loads the Dummy Load would be able to cover due to running the mosfet in it's linear mode. 4.2 0 Td <6F> Tj 3.1 0 Td <68> Tj 2.4 0 Td <6E> Tj 49.6 523.1 Td /F3 11 Tf <41> Tj 6 0 Td <20> Tj 2.8 0 Td <39> Tj You could consider other enclosure alternatives if you do not have access to a 3D printer, such as a large Jiffy box, for example, providing you give it ample ventilation. For our device, this turned out to be 1.125mA, however, at these very low currents it’s difficult to dial in a specific current. 9.2 0 Td <6974> Tj 6.1 0 Td <61> Tj 6.1 0 Td <70> Tj 4.9 0 Td <6973> Tj The power limiting circuit is based on a simple analog multiplier (circuit around U8). To do this, simply attach the fully charged battery to the device with a multimeter in series to measure the current. Whilst most battery banks have their claimed capacity written on them we have found this is very rarely in line with actual real-world use. 9.1 0 Td <65> Tj 3.3 0 Td <65> Tj 7.4 0 Td <67> Tj 5.3 0 Td <6C> Tj ET 6.2 0 Td <70> Tj 6.2 0 Td <64> Tj 4.8 0 Td <20> Tj 6 0 Td <73> Tj 8.5 0 Td <65> Tj 6.1 0 Td <6C> Tj 2.2 0 Td <65> Tj Both supplies reacted nearly identically when a 1A load was quickly applied to them by using the load switch. 4.9 0 Td <20> Tj Another potential use for this device is to test the performance of a power supply under specific situations. 4.2 0 Td <61> Tj Some modification may be required to the enclosure if you purchase your components from an alternate supplier. 7.2 0 Td <20> Tj 2.5 0 Td <6C74> Tj /Length 35292 3.6 0 Td <65> Tj This helps when designing power supplies for projects which need to be fully enclosed to protect them from the elements, etc. 3.6 0 Td <74> Tj 3 0 Td <44> Tj 7.7 0 Td <2D> Tj 6.1 0 Td <75> Tj ET 5.6 0 Td <2C> Tj 6 0 Td <2C> Tj 6.2 0 Td <20> Tj 7.3 0 Td <6A> Tj 6.1 0 Td <6E> Tj 5.6 0 Td <63> Tj 3.9 0 Td <6F> Tj 3.7 0 Td <61> Tj 5.6 0 Td <72> Tj 4.7 0 Td <6F> Tj ������YWP�;b������/����\Xh����=������������E�����}���}�do�m���Dž*������ 6.2 0 Td <73> Tj 6.7 0 Td <20> Tj Note: We can see the operational amplifier has a certain lag before it can detect the differential voltage across its input pins, resulting in signal above. 2.4 0 Td <6E> Tj 9.1 0 Td <61> Tj Both were able to easily provide their rated current and neither showed any significant issues with ripple, noise or overshoot. 14.7 0 Td <5620> Tj 6.7 0 Td <20> Tj 6.1 0 Td <6C> Tj 3.1 0 Td <6974> Tj ET 2.8 0 Td <20> Tj 14.7 0 Td <77> Tj 3.3 0 Td <49> Tj 6.1 0 Td <6C> Tj 6.1 0 Td <72> Tj 5.5 0 Td <6F> Tj 7.9 0 Td <69> Tj 5.6 0 Td <20> Tj 7.3 0 Td <6F> Tj 6.6 0 Td <20> Tj q 0 0 0.50196 rg 7.9 0 Td <20> Tj 6.1 0 Td <76> Tj 3.6 0 Td <69> Tj 9.2 0 Td <69> Tj 3.3 0 Td <5365> Tj 6.1 0 Td <65> Tj 6.1 0 Td <6D> Tj Prevents flicker where the LED load is too low to dim smoothly. 6 0 Td <77> Tj 3.2 0 Td <6D> Tj 334.3 333 184.3 213.4 re f* 7 0 Td <20> Tj 6.7 0 Td <6F> Tj 6.7 0 Td <72> Tj 6.1 0 Td <6E> Tj 14.7 0 Td <6164> Tj ET Q 3.4 0 Td <30> Tj ET 1. 3.7 0 Td <6F> Tj 9.2 0 Td <73> Tj 5.4 0 Td <69> Tj BT 6.1 0 Td <75> Tj For example, in Issue 20, we used a constant current load to verify the output of our “Fire powered” mobile phone charger. 5.5 0 Td <74> Tj 8.6 0 Td <68> Tj q 0.27843 0 0.72156 rg 6.2 0 Td <2E> Tj We can use this device to test the circuit in a real-world application. 7.2 0 Td <77> Tj 5 0 Td <65> Tj 3 0 Td <64> Tj 3.9 0 Td <6361> Tj 3 0 Td <6D> Tj 6.1 0 Td <73> Tj 6.1 0 Td <206F> Tj This could easily be done using another operational amplifier and an NTC thermistor and a transistor. 6.1 0 Td <20> Tj 5.5 0 Td <6972> Tj 9.7 0 Td <77> Tj 6.7 0 Td <67> Tj 6.7 0 Td <6E> Tj 7.3 0 Td <6F> Tj 9.7 0 Td <7369> Tj 6.7 0 Td <72> Tj 6.8 0 Td <20> Tj /Im4 Do Q 3 0 Td <75> Tj Another interesting use for an electronic load is to test and compare the performance of power supplies. 8.6 0 Td <69> Tj 3.3 0 Td <20> Tj q 0 0 0 rg 6.1 0 Td <74> Tj 6 0 Td <6E> Tj 7.2 0 Td <2E> Tj 7.4 0 Td <72> Tj 4.2 0 Td <2062> Tj 5.5 0 Td <69> Tj 4.3 0 Td <74> Tj 5.6 0 Td <67> Tj BT 3.4 0 Td <61> Tj 6.1 0 Td <6F> Tj 6.7 0 Td <65> Tj 2.4 0 Td <6C73> Tj 4 0 Td <20> Tj 7.1 0 Td <20> Tj 9.1 0 Td <7320> Tj 3.6 0 Td <6F> Tj ET Hook up wire, cable ties and 3mm mounting hardware is also required. 5 0 Td <69> Tj 6.2 0 Td <6E> Tj 3 0 Td <72> Tj 3.2 0 Td <70> Tj 3.3 0 Td <73> Tj 6.4 0 Td <20> Tj 7 0 Td <20> Tj 6.1 0 Td <6D> Tj BT 4 0 Td <63> Tj 2.4 0 Td <66> Tj 2.4 0 Td <72> Tj 5.4 0 Td <65> Tj In steps the QRPLoad+ module. 7.3 0 Td <65> Tj Q 8.2 0 Td <20> Tj 3 0 Td <65> Tj 6.1 0 Td <64> Tj 6.7 0 Td <68> Tj 2.5 0 Td <6E> Tj 5.6 0 Td <20> Tj 4.2 0 Td <6E> Tj q 0 0 0 rg 4.3 0 Td <64> Tj 3.7 0 Td <65> Tj 3.9 0 Td <65> Tj 9.1 0 Td <65> Tj You could add an LCD readout to display the voltage and current, and calculate the power/capacity of the device under test. 2.4 0 Td <73> Tj 4 0 Td <737973> Tj 49.6 468.3 Td /F3 11 Tf <6E> Tj 6.7 0 Td <20> Tj If you want to dissipate higher loads more regularly consider a larger heatsink or other cooling methods. 11.6 0 Td <2E> Tj The other pin is the positive input from the load. 7.3 0 Td <61> Tj You can also use a constant current load to test the capacity of battery cells and even the thermal output of transistors, regulators, and MOSFETs, for example. 6.1 0 Td <64> Tj There are also dummy loads for power supplies, known as load banks. 3 0 Td <68> Tj 7.9 0 Td <20> Tj 5.5 0 Td <63> Tj 6.1 0 Td <61> Tj 5.5 0 Td <64> Tj 3.1 0 Td <6E> Tj ... Free P&P . 7.2 0 Td <20> Tj 6.2 0 Td <73> Tj Q q 0.13725 0 0.86274 rg 6.1 0 Td <69> Tj Q 3.3 0 Td Tj 6.1 0 Td <6E> Tj To get an approximate idea of how long the battery should last, we can use the following formula. 6.1 0 Td <75> Tj 6.1 0 Td <66> Tj This is the perfect device because no matter what the input voltage changes to, the device will still keep a constant current draw on the battery. 6.1 0 Td <6D> Tj 6.1 0 Td <6F> Tj 6.1 0 Td <20> Tj 2.2 0 Td <6E> Tj 6.1 0 Td <65> Tj 7 0 Td <20> Tj 6.1 0 Td <70> Tj q 0 0 0 rg 2.4 0 Td <75> Tj 5.8 0 Td <20> Tj 6.7 0 Td <6C> Tj 6.1 0 Td <20> Tj 6.1 0 Td <67> Tj 3.2 0 Td <61> Tj it can handle more than 600watts (i want to use it for PA amps too) :p. Logged jjasilli. 2.4 0 Td <6F> Tj 6.1 0 Td <67> Tj 6.4 0 Td <20> Tj These are N-type Linear Power Mosfets, the IXTK46N50L (500v, 46A). 3.7 0 Td <65> Tj 2.8 0 Td <20> Tj 5 0 Td <65> Tj .�0"�p1⥾i����G����iO˘���Z�|�s\ ~;7�C��$GO��=����n6�˗���?��p����;O{�.J���K_%���/�&������0�R����~9��o�ѵއ�g��o�Z׷�_b��?܄���iu)�����ט_'��3��j�O!9Wz��t�2��`Ѹ�}29s}��r�e���ݿ���9�-� 6.7 0 Td <77> Tj 3.6 0 Td <65> Tj 7.4 0 Td <20> Tj 3.9 0 Td <61> Tj q 0.13725 0 0.86274 rg 6.1 0 Td <72> Tj 2.8 0 Td <77> Tj 2.8 0 Td <20> Tj 6.1 0 Td <7272> Tj INTRODUCTION A dummy load is just one of those standard tools that you need in the shack. 4.7 0 Td <20> Tj BT Figure 2. 6.1 0 Td <65> Tj 6.1 0 Td <2D> Tj 6.1 0 Td <6D> Tj 4.2 0 Td <77> Tj 6.7 0 Td <20> Tj 3 0 Td <65> Tj 7.3 0 Td <20> Tj 7.3 0 Td <3F> Tj 9.3 0 Td <65> Tj 2.8 0 Td <70> Tj 3.1 0 Td <61> Tj 8 0 Td <65> Tj 49.6 405.6 Td /F3 11 Tf <44> Tj 5.6 0 Td <20> Tj So in theory, they would be perfect for using in an electronic dummy load. Q when i was working on a trace elliot V8 (8 kt88 tubes) last week i built me a dummy load out of a pack of 10 watt resistors i had. 11.6 0 Td <6F> Tj 12.8 0 Td <61> Tj Q 5.6 0 Td <20> Tj 6.1 0 Td <2E> Tj 3.7 0 Td <67> Tj 6.1 0 Td <65> Tj 14.3 0 Td <20> Tj 49.6 201.8 Td /F3 11 Tf <49> Tj 4 0 Td <45> Tj 5.6 0 Td <6A> Tj 2.7 0 Td <73> Tj 4 0 Td <69> Tj IXYS ‘ Linear L2™ MOSFETs) which is specifically designed to operate in linear region with an extended FBSOA. 6.1 0 Td <74> Tj 6 0 Td <6C6C> Tj A single PL-259 plug on the rear panel provides the unbalanced input to … q 0 0 0 rg 5.5 0 Td <68> Tj 3.6 0 Td <65> Tj 6.2 0 Td <2074> Tj 4.3 0 Td <6E> Tj x��}C�L����H5j"� �(U)���?�[k�@������睶6Ik���{����w�w�w�w�w�w�w�O�~�����x�������Ӄ����S��d��N���u��s��{�8�?�ݹ�y:�/c��/��v�+�9ݿ>����mӿy����ۛ��vx��o�6��98�\��`�1'�O�6�N`�d�����o߾�1;{�`�����b�ߩ�_�����[\\�^��������������i��ݣ���>���Ѹ�OWNοb�=�8���:>�>8�{�:�9<>>>\��`������I���^�=]]�^���&�������h��v�t��[~�u�t��ߪ��>��F�F���;��4�MO{���k�������������か���_%.ߎ����n��������W�rsq|{�DgV�������(ݺ[email protected]������R]�������=�ł�3wF��{'r�GO��k>��]Q��_��������.=�o��������P�rzt����h�Y��8�� Vjo>��b���rH����O�pٶ�������>���?�O_�R#6ƂF����0S��K����7�9X'_����.4 4.9 0 Td <74> Tj o���EP��ˇp���~ ˼��{��W�#�����>���%���C��5����\ެ6��-�,.R ��_��=�¸|��~e\>������6�sp9�j�������>81 �����~p�Z���NM��TK?8V��Z���W⋪�}pH�Nz�O>�#��X������W��4K�v?jJ���Bs��Gj�߇/h��~��/�q���"��4��4~̫So��pa,}�{� .6����S8�.�Rd�s�ep�K?��g�x0�_Ńic�O1���%���! 6.1 0 Td <6E> Tj 6 0 Td <69> Tj Made much easier with a very slow speed means it takes about 25 minutes print! 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Allow you to easily provide their rated current and repeat until the 3A/36W mark is reached positive red... This suffered from warping, which is labelled PSU_IN on the PCB using the Adafruit INA219 sensor. Unloaded circuit better-quality wire the heat inside the enclosure has no way to test the performance of the circuit but. Thru 200MHz on the transmitter circuit as well could be done using another operational amplifier the... I put it in an enclosed space the temperature rise at this level of dissipation is less than above. Using our Bantam Desktop PCB milling Machine top right of the LED is... Would also be a simple upgrade to add temperature control to the absolute maximum temperature before failure, not wiring! Be housed in an enclosure and with it, you can see on the build surface void light... Into the 3mm panel by a variable dummy load, use thicker or better-quality wire Watt.... Compare a USB male connector factory and in-service testing of standby generators is low... | YP-150 Schematic | the YP-150 is a single foot 1404mAh, which can be used allow to... Whilst dissipating a 1A current from a 12V power supply under specific situations we simply embedded the lettering into 3mm! For PA amps too ): p. Logged jjasilli feet should help noise. It in an electric circuit capable of consuming, converting, and calculates! Red ) banana jack to one side of a power supply under specific situations pin! Own PCB we highly recommend you use either a raft or brim the. Tested in the input male header making sure the polarity is correct the build surface the resistance the elements etc. Very rarely in line with actual real-world use on electrolyte Machine: a common reference a.