diff --git a/src/app/app.module.ts b/src/app/app.module.ts
index d51f858..b68abea 100644
--- a/src/app/app.module.ts
+++ b/src/app/app.module.ts
@@ -60,6 +60,8 @@ import { ReferenceTableComponent } from './components/reference-table/reference-
 import { MatSnackBarModule } from '@angular/material/snack-bar';
 import { EquipmentComponent } from './pages/tables/equipment/equipment.component';
 import { TimeFramesComponent } from './pages/tables/time-frames/time-frames.component';
+import { NumberRangeCellComponent } from './components/tableComponents/number-range-cell/number-range-cell.component';
+import { DateRangeCellComponent } from './components/tableComponents/date-range-cell/date-range-cell.component';
 
 
 
@@ -84,6 +86,8 @@ import { TimeFramesComponent } from './pages/tables/time-frames/time-frames.comp
     ReferenceTableComponent,
     EquipmentComponent,
     TimeFramesComponent,
+    NumberRangeCellComponent,
+    DateRangeCellComponent,
   ],
   imports: [
     BrowserModule,
diff --git a/src/app/components/data-page/data-page.component.html b/src/app/components/data-page/data-page.component.html
index 39b5fb5..1dbbd37 100644
--- a/src/app/components/data-page/data-page.component.html
+++ b/src/app/components/data-page/data-page.component.html
@@ -14,14 +14,25 @@
   <ng-container *ngFor="let object of propertiesInfo">
     <mat-card class="inline-card" *ngIf="object.type === 'Group'">
       <mat-card-title>{{ object.title }}</mat-card-title>
-
-      <app-cell
-        *ngFor="let prop of object.properties"
-        [editable]="data.isLockedByMe && !prop.readonly"
-        [(value)]="data[prop.dataPath]"
-        [label]="prop.translation || prop.dataPath"
-        [inputType]="prop.type"
-      ></app-cell>
+      <ng-container *ngFor="let prop of object.properties">
+        <app-cell
+          *ngIf="prop.type !== 'NumRange'"
+          [editable]="data.isLockedByMe && prop.acceptedForUpdating"
+          [required]="prop.requiredForUpdating"
+          (validityChange)="validityChange(prop.dataPath, $event)"
+          [(value)]="data[prop.dataPath]"
+          [label]="prop.translation || prop.dataPath"
+          [inputType]="prop.type"
+        ></app-cell>
+        <app-number-range-cell
+          *ngIf="prop.type === 'NumRange'"
+          [editable]="data.isLockedByMe && prop.acceptedForUpdating"
+          (validityChange)="validityChange(prop.dataPath, $event)"
+          [(min)]="data[prop.dataPath + '.min']"
+          [(max)]="data[prop.dataPath + '.max']"
+          [label]="prop.translation || prop.dataPath"
+        ></app-number-range-cell
+      ></ng-container>
     </mat-card>
 
     <mat-card class="inline-card" *ngIf="object.type === 'ReferenceTable'">
@@ -32,7 +43,9 @@
           *ngIf="object.linkToTable"
           color="primary"
           [routerLink]="object.linkToTable(data)"
-          [queryParams]="object.linkToTableParams ? object.linkToTableParams(data) : {}"
+          [queryParams]="
+            object.linkToTableParams ? object.linkToTableParams(data) : {}
+          "
           matTooltip="Zur Tabelle"
         >
           <mat-icon>subdirectory_arrow_right</mat-icon>
@@ -83,15 +96,26 @@
   >
     <mat-icon>cancel</mat-icon>
   </button>
-  <button
-    mat-fab
-    (click)="save()"
+  <div
     *ngIf="data.isLockedByMe"
-    class="floating-fab-button"
-    [disabled]="isSavingOrLocking || isLoading"
+    [matTooltip]="
+      countUnvalidProperties() > 0
+        ? 'Ungültige oder nicht ausgefüllte Pflichtfelder (rot): ' +
+          countUnvalidProperties()
+        : 'Abspeichern'
+    "
   >
-    <mat-icon>save</mat-icon>
-  </button>
+    <button
+      mat-fab
+      (click)="save()"
+      class="floating-fab-button"
+      [disabled]="
+        isSavingOrLocking || isLoading || countUnvalidProperties() > 0
+      "
+    >
+      <mat-icon>save</mat-icon>
+    </button>
+  </div>
   <button
     mat-fab
     *ngIf="data.isLocked"
diff --git a/src/app/components/data-page/data-page.component.ts b/src/app/components/data-page/data-page.component.ts
index dc2736f..6f13180 100644
--- a/src/app/components/data-page/data-page.component.ts
+++ b/src/app/components/data-page/data-page.component.ts
@@ -1,4 +1,11 @@
-import { Component, EventEmitter, Input, OnDestroy, OnInit, Output } from '@angular/core';
+import {
+  Component,
+  EventEmitter,
+  Input,
+  OnDestroy,
+  OnInit,
+  Output,
+} from '@angular/core';
 import { ActivatedRoute } from '@angular/router';
 import { deepen } from 'src/app/helperFunctions/deepenObject';
 import { flatten } from 'src/app/helperFunctions/flattenObject';
@@ -7,7 +14,8 @@ import { SchemaService } from 'src/app/services/schema.service';
 interface PropertyTypeInfo {
   dataPath: string;
   translation: string;
-  readonly?: boolean;
+  acceptedForUpdating?: boolean;
+  requiredForUpdating?: boolean;
   type?: string;
 }
 
@@ -61,6 +69,8 @@ export class DataPageComponent implements OnInit, OnDestroy {
   isLoading: boolean = false;
   isSavingOrLocking: boolean = false;
 
+  propertyValidity = {};
+
   constructor(
     private route: ActivatedRoute,
     private schemaService: SchemaService
@@ -115,7 +125,14 @@ export class DataPageComponent implements OnInit, OnDestroy {
           this.pageDataGQLUpdateInputType,
           prop.dataPath
         );
-        prop.readonly = prop.readonly || !updateTypeInformation.isPartOfType;
+        prop.acceptedForUpdating =
+          prop.acceptedForUpdating != null
+            ? prop.acceptedForUpdating
+            : updateTypeInformation.isPartOfType;
+        prop.requiredForUpdating =
+          prop.requiredForUpdating != null
+            ? prop.requiredForUpdating
+            : updateTypeInformation.isRequired;
       }
     }
   }
@@ -124,6 +141,20 @@ export class DataPageComponent implements OnInit, OnDestroy {
     this.lockEvent.emit(deepen(this.data));
   }
 
+  validityChange(columnName: string, isValid: Event) {
+    this.propertyValidity[columnName] = isValid;
+  }
+
+  countUnvalidProperties() {
+    let unvalidFieldsCount = 0;
+    for (const prop in this.propertyValidity) {
+      if (!this.propertyValidity[prop]) {
+        unvalidFieldsCount++;
+      }
+    }
+    return unvalidFieldsCount;
+  }
+
   save() {
     this.saveEvent.emit(
       this.schemaService.filterObject(
diff --git a/src/app/components/table/table.component.html b/src/app/components/table/table.component.html
index 1569447..cc31737 100644
--- a/src/app/components/table/table.component.html
+++ b/src/app/components/table/table.component.html
@@ -116,34 +116,59 @@
           {{ getTranslation(column.dataPath) }}
         </th>
         <td mat-cell *matCellDef="let element">
-          <app-cell
-            *ngIf="
-              column.type === 'DateRange' ||
-              column.type === 'Boolean' ||
-                element.newObject ||
-                (!column.readonly && element.isLockedByMe);
-              else stringValue
-            "
-            [editable]="
-              (element.newObject && column.acceptedForCreation) ||
-              (!column.readonly && element.isLockedByMe)
-            "
-            [required]="element.newObject && column.requiredForCreation"
-            (validityChange)="validityChange(element, column.dataPath, $event)"
-            [(value)]="element[column.dataPath]"
-            [inputType]="column.type"
-            [link]="column.link ? column.link(element) : null"
-          ></app-cell>
-          <ng-template #stringValue>
-            <span *ngIf="!column.link">{{ element[column.dataPath] }}</span>
-            <a
-              mat-button
-              color="primary"
-              *ngIf="column.link"
-              [routerLink]="column.link(element)"
-              >{{ element[column.dataPath] }}</a
-            >
-          </ng-template>
+          <ng-container
+            *ngIf="column.type !== 'DateRange' && column.type !== 'NumRange'"
+          >
+            <app-cell
+              *ngIf="
+                column.type === 'Boolean' ||
+                  (element.newObject && column.acceptedForCreation) ||
+                  (column.acceptedForUpdating && element.isLockedByMe);
+                else stringValue
+              "
+              [editable]="
+                (element.newObject && column.acceptedForCreation) ||
+                (column.acceptedForUpdating && element.isLockedByMe)
+              "
+              [required]="
+                (element.newObject && column.requiredForCreation) ||
+                (element.isLockedByMe && column.requiredForCreation)
+              "
+              (validityChange)="
+                validityChange(element, column.dataPath, $event)
+              "
+              [(value)]="element[column.dataPath]"
+              [inputType]="column.type"
+              [link]="column.link ? column.link(element) : null"
+            ></app-cell>
+            <ng-template #stringValue>
+              <span *ngIf="!column.link">{{ element[column.dataPath] }}</span>
+              <a
+                mat-button
+                color="primary"
+                *ngIf="column.link"
+                [routerLink]="column.link(element)"
+                >{{ element[column.dataPath] }}</a
+              >
+            </ng-template>
+          </ng-container>
+          <ng-container *ngIf="column.type === 'NumRange'">
+            <app-number-range-cell
+              [editable]="
+                (element.newObject && column.acceptedForCreation) ||
+                (column.acceptedForUpdating && element.isLockedByMe)
+              "
+              [required]="
+                (element.newObject && column.requiredForCreation) ||
+                (element.isLockedByMe && column.requiredForCreation)
+              "
+              (validityChange)="
+                validityChange(element, column.dataPath, $event)
+              "
+              [(min)]="element[column.dataPath + '.min']"
+              [(max)]="element[column.dataPath + '.max']"
+            ></app-number-range-cell>
+          </ng-container>
         </td>
       </ng-container>
 
@@ -190,14 +215,23 @@
               [diameter]="32"
               *ngIf="isLoading(element.id)"
             ></mat-spinner>
-
-            <button
-              mat-icon-button
+            <div
               *ngIf="element.isLockedByMe && !isLoading(element.id)"
-              (click)="save(element)"
+              [matTooltip]="
+                countUnvalidFields(element) > 0
+                  ? 'Ungültige oder nicht ausgefüllte Pflichtfelder (rot): ' +
+                    countUnvalidFields(element)
+                  : 'Abspeichern'
+              "
             >
-              <mat-icon>save</mat-icon>
-            </button>
+              <button
+                mat-icon-button
+                [disabled]="countUnvalidFields(element) > 0"
+                (click)="save(element)"
+              >
+                <mat-icon>save</mat-icon>
+              </button>
+            </div>
             <button
               mat-icon-button
               matTooltip="Alle ungespeicherten Änderungen verwerfen."
@@ -218,7 +252,7 @@
             *ngIf="element.newObject"
             [matTooltip]="
               countUnvalidFields(element) > 0
-                ? 'Nicht ausgefüllte Pflichtfelder (rot): ' +
+                ? 'Ungültige oder nicht ausgefüllte Pflichtfelder (rot): ' +
                   countUnvalidFields(element)
                 : 'Erstellen'
             "
diff --git a/src/app/components/table/table.component.ts b/src/app/components/table/table.component.ts
index 7219fc7..70a5ed9 100644
--- a/src/app/components/table/table.component.ts
+++ b/src/app/components/table/table.component.ts
@@ -20,6 +20,7 @@ import { MatDialog, MatDialogRef } from '@angular/material/dialog';
 import { ActivatedRoute } from '@angular/router';
 import { Subject } from 'rxjs';
 import { debounceTime } from 'rxjs/internal/operators/debounceTime';
+import { type } from 'os';
 
 @Component({
   selector: 'app-table',
@@ -37,7 +38,8 @@ export class TableComponent implements AfterViewInit {
     acceptedForCreation?: boolean;
     requiredForCreation?: boolean;
     sticky?: boolean;
-    readonly?: boolean;
+    acceptedForUpdating?: boolean;
+    requiredForUpdating?: boolean;
     type?: string;
     link?: (row: any) => string;
   }[] = [];
@@ -193,7 +195,14 @@ export class TableComponent implements AfterViewInit {
         this.tableDataGQLUpdateInputType,
         column.dataPath
       );
-      column.readonly = column.readonly !== null ? column.readonly : !typeInformation.isPartOfType;
+      column.acceptedForUpdating =
+        column.acceptedForUpdating != null
+          ? column.acceptedForUpdating
+          : typeInformation.isPartOfType;
+      column.requiredForUpdating =
+        column.requiredForUpdating != null
+          ? column.requiredForUpdating
+          : typeInformation.isRequired;
     }
     for (const column of this.columnInfo) {
       const typeInformation = this.schemaService.getTypeInformation(
@@ -201,9 +210,13 @@ export class TableComponent implements AfterViewInit {
         column.dataPath
       );
       column.requiredForCreation =
-        column.requiredForCreation || typeInformation.isRequired;
+        column.requiredForCreation != null
+          ? column.requiredForCreation
+          : typeInformation.isRequired;
       column.acceptedForCreation =
-        column.acceptedForCreation || typeInformation.isPartOfType;
+        column.acceptedForCreation != null
+          ? column.acceptedForCreation
+          : typeInformation.isPartOfType;
     }
   }
 
@@ -235,7 +248,7 @@ export class TableComponent implements AfterViewInit {
   countUnvalidFields(row: any) {
     let unvalidFieldsCount = 0;
     if (!row.FieldsValidity) {
-      return 99;
+      return 0;
     }
     for (const prop in row.FieldsValidity) {
       if (!row.FieldsValidity[prop]) {
diff --git a/src/app/components/tableComponents/cell/cell.component.html b/src/app/components/tableComponents/cell/cell.component.html
index ed20040..4664825 100644
--- a/src/app/components/tableComponents/cell/cell.component.html
+++ b/src/app/components/tableComponents/cell/cell.component.html
@@ -55,31 +55,6 @@
   </mat-form-field>
 </ng-container>
 
-<div *ngIf="htmlInputType === 'numberRange'" class="number-range-wrapper">
-  <mat-form-field class="number-range-form-field">
-    <mat-label *ngIf="label">{{ label }}</mat-label>
-    <input
-      matInput
-      type="number"
-      [disabled]="!editable"
-      [value]="value.min"
-      (input)="minValueChange($event)"
-      [required]="required"
-    />
-  </mat-form-field>
-  <span class="range-spacer">-</span>
-  <mat-form-field class="number-range-form-field">
-    <input
-      matInput
-      type="number"
-      [disabled]="!editable"
-      [value]="value.max"
-      (input)="maxValueChange($event)"
-      [required]="required"
-    />
-  </mat-form-field>
-</div>
-
 <div
   #otherInputType
   *ngIf="htmlInputType === 'number' || htmlInputType === 'text'"
diff --git a/src/app/components/tableComponents/cell/cell.component.scss b/src/app/components/tableComponents/cell/cell.component.scss
index 478572b..e69de29 100644
--- a/src/app/components/tableComponents/cell/cell.component.scss
+++ b/src/app/components/tableComponents/cell/cell.component.scss
@@ -1,8 +0,0 @@
-.number-range-wrapper {
-    display: flex;
-    flex-direction: row;
-    align-items: center;
-  .range-spacer {
-    margin: 0 0.5em;
-  }
-}
diff --git a/src/app/components/tableComponents/cell/cell.component.ts b/src/app/components/tableComponents/cell/cell.component.ts
index cc3210a..9a29c48 100644
--- a/src/app/components/tableComponents/cell/cell.component.ts
+++ b/src/app/components/tableComponents/cell/cell.component.ts
@@ -9,6 +9,7 @@ import {
   ChangeDetectorRef,
   AfterViewInit,
 } from '@angular/core';
+import { FormControl, FormGroup, Validators } from '@angular/forms';
 
 @Component({
   selector: 'app-cell',
@@ -17,7 +18,18 @@ import {
 })
 export class CellComponent implements AfterViewInit {
   @Input()
-  value: any; // number | string | boolean | { start: string; end: string; };
+  set value(value: any) {
+    this._value = value;
+    setTimeout(() => {
+      this.checkIfValid();
+    });
+  } // number | string | boolean | { start: string; end: string; };
+  get value(): any {
+    return this._value;
+  }
+  _value: any;
+
+  rangeForm: FormGroup;
   minValue: number;
   maxValue: number;
 
@@ -52,6 +64,8 @@ export class CellComponent implements AfterViewInit {
 
   constructor(private cdr: ChangeDetectorRef, public datepipe: DatePipe) {}
 
+  ngOnInit() {}
+
   ngAfterViewInit(): void {
     if (this.required) {
       this.input?.control?.markAsTouched();
@@ -93,6 +107,12 @@ export class CellComponent implements AfterViewInit {
       ) {
         this.value = { min: null, max: null };
       }
+      this.rangeForm = new FormGroup({
+        minValue: new FormControl(),
+        maxValue: new FormControl(),
+      });
+      this.rangeForm.controls['minValue'].markAsTouched();
+      this.rangeForm.controls['maxValue'].markAsTouched();
     }
   }
 
@@ -125,16 +145,38 @@ export class CellComponent implements AfterViewInit {
   }
 
   minValueChange(event) {
-    this.value.min = this.toNumber(event.target.value);
+    this.value.min = Math.abs(this.toNumber(event.target.value));
     this.valueChange.emit(this.value);
-    console.log(this.value);
+    this.checkIfRangeIsValid();
   }
 
   maxValueChange(event) {
-    this.value.max = this.toNumber(event.target.value);
+    this.value.max = Math.abs(this.toNumber(event.target.value));
     this.valueChange.emit(this.value);
-    console.log(this.value);
+    this.checkIfRangeIsValid();
+  }
 
+  checkIfRangeIsValid() {
+    if (this.value.min === null || this.value.max === null) {
+      this.setRangeError(false);
+      return;
+    }
+    if (this.value.min <= this.value.max) {
+      this.setRangeError(false);
+      return;
+    }
+    this.setRangeError(true);
+  }
+
+  setRangeError(error: boolean): void {
+    this.validityChange.emit(!error);
+    if (error) {
+      this.rangeForm.controls['minValue'].setErrors({ rangeError: true });
+      this.rangeForm.controls['maxValue'].setErrors({ rangeError: true });
+    } else {
+      this.rangeForm.controls['minValue'].setErrors(null);
+      this.rangeForm.controls['maxValue'].setErrors(null);
+    }
   }
 
   transformDate(date) {
diff --git a/src/app/components/tableComponents/date-range-cell/date-range-cell.component.html b/src/app/components/tableComponents/date-range-cell/date-range-cell.component.html
new file mode 100644
index 0000000..a1b96fb
--- /dev/null
+++ b/src/app/components/tableComponents/date-range-cell/date-range-cell.component.html
@@ -0,0 +1 @@
+<p>date-range-cell works!</p>
diff --git a/src/app/components/tableComponents/date-range-cell/date-range-cell.component.scss b/src/app/components/tableComponents/date-range-cell/date-range-cell.component.scss
new file mode 100644
index 0000000..e69de29
diff --git a/src/app/components/tableComponents/date-range-cell/date-range-cell.component.ts b/src/app/components/tableComponents/date-range-cell/date-range-cell.component.ts
new file mode 100644
index 0000000..82be446
--- /dev/null
+++ b/src/app/components/tableComponents/date-range-cell/date-range-cell.component.ts
@@ -0,0 +1,15 @@
+import { Component, OnInit } from '@angular/core';
+
+@Component({
+  selector: 'app-date-range-cell',
+  templateUrl: './date-range-cell.component.html',
+  styleUrls: ['./date-range-cell.component.scss']
+})
+export class DateRangeCellComponent implements OnInit {
+
+  constructor() { }
+
+  ngOnInit(): void {
+  }
+
+}
diff --git a/src/app/components/tableComponents/number-range-cell/number-range-cell.component.html b/src/app/components/tableComponents/number-range-cell/number-range-cell.component.html
new file mode 100644
index 0000000..d4ebae0
--- /dev/null
+++ b/src/app/components/tableComponents/number-range-cell/number-range-cell.component.html
@@ -0,0 +1,28 @@
+<div
+  *ngIf="editable || label"
+  class="number-range-wrapper"
+  [formGroup]="rangeForm"
+>
+  <mat-form-field class="number-range-form-field">
+    <mat-label *ngIf="label">{{ label }} min</mat-label>
+    <input
+      matInput
+      type="number"
+      formControlName="minValue"
+      (input)="minValueChange($event)"
+    />
+  </mat-form-field>
+  <span class="range-spacer">-</span>
+  <mat-form-field class="number-range-form-field">
+    <mat-label *ngIf="label">{{ label }} max</mat-label>
+    <input
+      matInput
+      formControlName="maxValue"
+      type="number"
+      (input)="maxValueChange($event)"
+    />
+  </mat-form-field>
+</div>
+<div *ngIf="!editable && !label">
+  {{ min }} - {{ max }}
+</div>
diff --git a/src/app/components/tableComponents/number-range-cell/number-range-cell.component.scss b/src/app/components/tableComponents/number-range-cell/number-range-cell.component.scss
new file mode 100644
index 0000000..478572b
--- /dev/null
+++ b/src/app/components/tableComponents/number-range-cell/number-range-cell.component.scss
@@ -0,0 +1,8 @@
+.number-range-wrapper {
+    display: flex;
+    flex-direction: row;
+    align-items: center;
+  .range-spacer {
+    margin: 0 0.5em;
+  }
+}
diff --git a/src/app/components/tableComponents/number-range-cell/number-range-cell.component.ts b/src/app/components/tableComponents/number-range-cell/number-range-cell.component.ts
new file mode 100644
index 0000000..1e376c7
--- /dev/null
+++ b/src/app/components/tableComponents/number-range-cell/number-range-cell.component.ts
@@ -0,0 +1,123 @@
+import { DatePipe } from '@angular/common';
+import {
+  Component,
+  Input,
+  Output,
+  EventEmitter,
+  ChangeDetectorRef,
+  OnInit,
+} from '@angular/core';
+import { FormControl, FormGroup, Validators } from '@angular/forms';
+
+@Component({
+  selector: 'app-number-range-cell',
+  templateUrl: './number-range-cell.component.html',
+  styleUrls: ['./number-range-cell.component.scss'],
+})
+export class NumberRangeCellComponent implements OnInit {
+  @Input()
+  set min(value: number) {
+    this._min = value;
+    this.rangeForm?.controls['minValue'].setValue(value);
+  }
+  get min() {
+    return this._min;
+  }
+  _min: number;
+
+  @Input()
+  set max(value: number) {
+    this._max = value;
+    this.rangeForm?.controls['maxValue'].setValue(value);
+  }
+  get max() {
+    return this._max;
+  }
+  _max: number;
+
+  rangeForm: FormGroup;
+
+  @Output() minChange = new EventEmitter<number>();
+  @Output() maxChange = new EventEmitter<number>();
+
+  @Input()
+  set editable(value) {
+    this._editable = value;
+    if (value) {
+      this.rangeForm?.controls['minValue'].enable();
+      this.rangeForm?.controls['maxValue'].enable();
+    } else {
+      this.rangeForm?.controls['minValue'].disable();
+      this.rangeForm?.controls['maxValue'].disable();
+    }
+  }
+  _editable = false;
+  get editable() {
+    return this._editable;
+  }
+  @Input()
+  required = false;
+  @Input()
+  label: string = null;
+  @Output() validityChange = new EventEmitter<boolean>();
+  isValid = true;
+
+  constructor(private cdr: ChangeDetectorRef, public datepipe: DatePipe) {}
+
+  ngOnInit() {
+    this.rangeForm = new FormGroup({
+      minValue: new FormControl(),
+      maxValue: new FormControl(),
+    });
+    this.rangeForm.controls['minValue'].markAsTouched();
+    this.rangeForm.controls['maxValue'].markAsTouched();
+    this.rangeForm?.controls['minValue'].setValue(this.min);
+    this.rangeForm?.controls['maxValue'].setValue(this.max);
+  }
+
+  minValueChange(event) {
+    this.min = this.toPositiveNumber(event.target.value);
+    this.minChange.emit(this.min);
+    this.checkIfRangeIsValid();
+  }
+
+  maxValueChange(event) {
+    this.max = this.toPositiveNumber(event.target.value);
+    this.maxChange.emit(this.max);
+    this.checkIfRangeIsValid();
+  }
+
+  checkIfRangeIsValid() {
+    if (this.min == null || this.max == null) {
+      this.setRangeError(false);
+      return;
+    }
+    if (this.min <= this.max) {
+      this.setRangeError(false);
+      return;
+    }
+    this.setRangeError(true);
+  }
+
+  setRangeError(error: boolean): void {
+    this.validityChange.emit(!error);
+    if (error) {
+      this.rangeForm.controls['minValue'].setErrors({ rangeError: true });
+      this.rangeForm.controls['maxValue'].setErrors({ rangeError: true });
+    } else {
+      this.rangeForm.controls['minValue'].setErrors(null);
+      this.rangeForm.controls['maxValue'].setErrors(null);
+    }
+  }
+
+  toPositiveNumber(str: string): number {
+    if (str === '') {
+      return null;
+    }
+    const number = +str;
+    if (number < 0) {
+      return Math.abs(number);
+    }
+    return number;
+  }
+}
diff --git a/src/app/pages/dataPages/bike/bike.component.ts b/src/app/pages/dataPages/bike/bike.component.ts
index f30155c..946f70b 100644
--- a/src/app/pages/dataPages/bike/bike.component.ts
+++ b/src/app/pages/dataPages/bike/bike.component.ts
@@ -60,7 +60,7 @@ export class BikeComponent implements OnInit {
     },
     {
       type: 'Group',
-      title: 'Maße und Ladungen',
+      title: 'Maße und Ladung',
       properties: [
         { dataPath: 'dimensionsAndLoad.bikeLength', translation: 'Länge' },
         { dataPath: 'dimensionsAndLoad.bikeWeight', translation: 'Gewicht' },
diff --git a/src/environments/environment.ts b/src/environments/environment.ts
index 1e77194..d2b673a 100644
--- a/src/environments/environment.ts
+++ b/src/environments/environment.ts
@@ -4,8 +4,8 @@
 
 export const environment = {
   production: false,
-  apiUrl: "https://flotte.duckdns.org", // without /graphql !!!
-  authUrl: "https://flotte.duckdns.org/user-management"
+  apiUrl: "http://173.212.197.169:4000", // without /graphql !!!
+  authUrl: "http://173.212.197.169:8080"
 };
 
 /*