# Updating RMS Value in Hypersim using Dashboard **URL:** \ **Category:** Q&A\ **Tags:** hypersim, discussion, protection-testing, testing-approaches\ **Created:** [October 12, 2026, 12:03pm UTC](https://community.opal-rt.com/t/updating-rms-value-in-hypersim-using-dashboard/261 "2026-10-12T12:03:41Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Suved](https://avatars.discourse-cdn.com/v4/letter/s/58f4c7/32.png) [@Suved](https://community.opal-rt.com/u/Suved)\ **Post date:** [October 12, 2026, 12:03pm UTC](https://community.opal-rt.com/t/updating-rms-value-in-hypersim-using-dashboard/261/1 "2026-10-12T12:03:41Z")
![T1.png](https://canada1.discourse-cdn.com/flex012/uploads/sps/original/1X/8311e6c2aeae11e971b6ce82456736a276fe75ea.png) Could you please guide me on how to change the RMS value of the sine wave generator in Hypersim software using the dashboard? I have attached a picture for reference and would like to update only the green-highlighted section. ---
**Author:** ![sorfina](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@sorfina](https://community.opal-rt.com/u/sorfina)\ **Post date:** [October 13, 2026, 2:43am UTC](https://community.opal-rt.com/t/updating-rms-value-in-hypersim-using-dashboard/261/2 "2026-10-13T02:43:25Z")
Hi Suved, In your screenshot, `=1*sqrt(2)` is the amplitude **A** , which is the **peak** value of the sine wave. The green **1** is the value you’re using as the RMS voltage, and `sqrt(2)` converts that RMS value into a peak value: **V\_peak = V\_RMS × √2** A Dashboard control can’t edit only one part of an expression like `=1*sqrt(2)`. It sends one complete numerical value to a block parameter. So if you want to control only the RMS value and keep the √2 conversion fixed, the best approach is to move the RMS value into its own block and connect the Dashboard control to that block. * * * ### Option 1 (recommended): Control the RMS with a Constant block **Step 1: Update the model** 1. Open the **Sine Wave Generator** block. 2. Change amplitude **A** from `=1*sqrt(2)` to `=sqrt(2)`. This keeps the √2 conversion fixed inside the Sine Wave Generator. 3. Add a **Constant** block to the model and name it `Vrms`. 4. Set the Constant block value to `1`. This block is now your controllable RMS value. 5. Add a **Product** block. 6. Connect: 7. Select the sensors on the Constant and Product blocks, then click **Analyze**. **Step 2: Configure the Dashboard** 1. Open **Dashboards**. If the Dashboard icon is greyed out, go to **Preferences** , check **Enable** , and restart HYPERSIM. 2. Under **Models** , select your model and click **Fetch Data**. 3. Under **Boards** , create a new panel. 4. Drag a control widget, such as a **Knob** or **Slider** , onto the panel. 5. Connect the widget to the `Vrms` Constant block sensor. 6. Set the widget’s minimum and maximum values to the RMS range you want to test. 7. (Optional) Add a **Graph** or **Numeric Display** connected to the Product output so you can watch the result while you change the RMS setting. 8. Start the simulation and adjust the knob or slider. The RMS value changes through the `Vrms` Constant block, and the √2 conversion stays fixed. * * * ### Option 2: Link amplitude A to the Constant block with an expression You can also link the Sine Wave Generator amplitude directly to the Constant block with an expression. Set amplitude **A** to: `=Vrms.ATTRIBUTE*sqrt(2)` To find the correct attribute name: 1. Hover over the Constant block’s value field. 2. The attribute name appears in square brackets. 3. Replace `ATTRIBUTE` with that name. This links the two values, so when you change the Constant block value, amplitude A is recalculated as V\_RMS × √2. **Important note about Option 2:** The documentation says the expression is recalculated when values are edited in HYPERSIM. It doesn’t clearly confirm whether a value sent from the Dashboard during a running simulation also recalculates amplitude A. It’s worth testing this first. If A doesn’t update while the simulation is running, use Option 1 instead. * * * ### What to avoid Don’t connect the Dashboard control directly to the Sine Wave Generator’s amplitude **A**. This overwrites the whole `=1*sqrt(2)` expression, so you would have to enter the **peak** value yourself (V\_peak = V\_RMS × 1.414) instead of the RMS value. Hope this helps! ---
**Author:** ![Suved](https://avatars.discourse-cdn.com/v4/letter/s/58f4c7/32.png) [@Suved](https://community.opal-rt.com/u/Suved)\ **Post date:** [October 14, 2026, 5:27am UTC](https://community.opal-rt.com/t/updating-rms-value-in-hypersim-using-dashboard/261/3 "2026-10-14T05:27:59Z")
@sorfina Thanks for the solution. Both options are good. Option 2 is more advanced. I will try option 2 if it works like option 1.