HP E3610 - Page 1
Forum section: electronics / repair

author: kingorcus
author_rank: Newbie
timestamp: February 21, 2023, 12:21:42 am
content: I just bough this unit from ebay. I am a beginner...I tested it today on a 12v car part and voltage dropped to 1.85v and it did not move the parthere is a video of the part connected to PS and another one connected to battery.Any ideas what the problem is?andIt looks like a PS issue, should I try to fix or return.Thansk much...

author: Chris56000
author_rank: Frequent Contributor
timestamp: February 21, 2023, 12:36:37 am
content: Hi!This power supply you have bought is totally unsuitable for testing car components like the solenoid actuator you've pictured, these have a very low resistance that acts like a direct short–circuit across the power supply, that is causing it to go straight into "current limit" mode!The ECUs/control units in the car(s) that operate these actuator/solenoid units contain special circuitry that discharges a large capacitor into the windings of the solenoid to start them moving, and then once they have started to move, they only need a much smaller "hold–in" current to keep them in the actuated position!The power supply you have bought is probably OK but simply too small to even attempt to test car components!If you do want to test it, if you get something like a 12 V car tail, reverse–light or indicator bulb from your local car spares store, your power supply should light a 12 V 21W bulb but it won't provide more than 2 A or about 2.5A at 12 V!Chris Williams

author: pqass
author_rank: Super Contributor
timestamp: February 21, 2023, 01:17:24 am
content: Chris56000 is correct about automotive loads generally. But, you show in your second video that the load is pulling 0.81A at 12V from the battery. The E3610 can do this. You just have turn the Current knob fully clockwise (to set a limit of up to 2A) and also push the Range button in (to allow you to source up to 15V). Upon initial connection, the CC LED may be briefly lit but should go back to CV mode.Alternatively, if you have a spare Personal Computer (ATX) power supply, they can provide many amps at 12V.https://wiert.me/2018/11/16/convert-adapt-an-old-atx-power-supply-into-a-bench-power-supply-with-or-without-3d-printed-parts/

author: kingorcus
author_rank: Newbie
timestamp: February 21, 2023, 02:06:05 am
content: Thanks guys:yes it was the current not set correctly.I am new to unit, I increased the current to 1.5 amps and it turned the solenoid on.so it depends on the car parts I am trying to power, anything that requires less than 2amps starting and maintaining I should be able to power correct?

author: pqass
author_rank: Super Contributor
timestamp: February 21, 2023, 02:12:20 am
content: Just an FYI as I think you may be new to bench/lab power supplies...These supplies allow you to set the max. voltage that will appear at the output terminals (left knob).However, it is the load that decides how much current to draw from the supply (at the set voltage) because resistance is a property of the load.But, you can put a cap on the current drawn (right knob).If the load decides to draw less current than the limit, the supply will show the voltage that was set and the current being drawn. But, if your load tries to pull more than the set current limit, then the supply will lower the voltage until the current drawn is at the set current limit. That is what is happening when you see 1.85V at 0.12A. The proof is: 1.85/0.12 = 12/x, solve for x=0.78 which is slightly lower than your reading with the 12V battery (likely because the battery is probably 12.something).Quote from: kingorcus on February 21, 2023, 02:06:05 amYes.

author: kingorcus
author_rank: Newbie
timestamp: February 21, 2023, 02:54:39 am
content: Thanks..I understand now..The cap on the current drawn was very low leading to this...