diff --git a/e2e/reset-param-mode.e2e-spec.ts b/e2e/reset-param-mode.e2e-spec.ts
index c4b7548394bbfc131bd31f03bf1ac399085cfab6..b6a294b72b6b920c7c407a53416f8c6746da89a1 100644
--- a/e2e/reset-param-mode.e2e-spec.ts
+++ b/e2e/reset-param-mode.e2e-spec.ts
@@ -13,12 +13,12 @@ describe("ngHyd - check parameter mode is set to its previous value - ", () => {
         listPage = new ListPage();
     });
 
-    it("when min/max/list values dialog is cancelled", async () => {
+    it("when min/max/list values dialog is cancelled on 'fish ladder: fall' calculator", async () => {
         // start page
         await listPage.navigateTo();
         await browser.sleep(500);
 
-        // open PAB chute
+        // open 'PAB fall' calculator
         await listPage.clickMenuEntryForCalcType(12);
         await browser.sleep(500);
 
@@ -37,10 +37,47 @@ describe("ngHyd - check parameter mode is set to its previous value - ", () => {
         await cancelbtn.click();
         await browser.sleep(200);
 
-        // check Z1 var toggle is disabled
+        // check Z1 var toggle is not checked
         expect(await z1varbtn.getAttribute("ng-reflect-checked")).toBe("false");
 
-        // check Z1 calc toggle is enabled
+        // check Z1 calc toggle is checked
+        expect(await z1calcbtn.getAttribute("ng-reflect-checked")).toBe("true");
+    });
+
+    it("when min/max/list values dialog is cancelled on 'fish ladder' calculator", async () => {
+        // start page
+        await listPage.navigateTo();
+        await browser.sleep(500);
+
+        // open PAB calculator
+        await listPage.clickMenuEntryForCalcType(15);
+        await browser.sleep(500);
+
+        // "fixed" radio on Q parameter
+        const qfixbtn = element(by.id("mat-button-toggle-1"));
+        await browser.sleep(50);
+
+        // "var" radio on Z1 parameter
+        const z1varbtn = element(by.id("mat-button-toggle-6"));
+        await browser.sleep(50);
+
+        // "calc" radio on Z1 parameter
+        const z1calcbtn = element(by.id("mat-button-toggle-7"));
+        await browser.sleep(50);
+
+        // click "var" radio on Z1 parameter
+        await z1varbtn.click();
+        await browser.sleep(200);
+
+        // click cancel button
+        const cancelbtn = element(by.id("btn-cancel"));
+        await cancelbtn.click();
+        await browser.sleep(200);
+
+        // check Q fix toggle is checked
+        expect(await qfixbtn.getAttribute("ng-reflect-checked")).toBe("true");
+
+        // check Z1 calc toggle is checked
         expect(await z1calcbtn.getAttribute("ng-reflect-checked")).toBe("true");
     });
 });
diff --git a/src/app/components/param-field-line/param-field-line.component.ts b/src/app/components/param-field-line/param-field-line.component.ts
index 1cb5750c7f0e1f33fa6b52b29a0a932d30f5d641..fa34f53ae026ea113fd34d65c8ee1a6d0594dbec 100644
--- a/src/app/components/param-field-line/param-field-line.component.ts
+++ b/src/app/components/param-field-line/param-field-line.component.ts
@@ -211,8 +211,13 @@ export class ParamFieldLineComponent implements OnChanges {
         let ret = true;
         if (this.param.paramDefinition.isCalculated) {
             const nub = this.param.paramDefinition.parentNub;
-            const p = nub.findFirstCalculableParameter(this.param.paramDefinition);
-            ret = (p !== undefined);
+            try {
+                const p = nub.findFirstCalculableParameter(this.param.paramDefinition);
+                ret = (p !== undefined);
+            }
+            catch (e) {
+                ret = true;
+            }
         }
         return ret;
     }