diff --git a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-data-keys-panel/modbus-data-keys-panel.component.html b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-data-keys-panel/modbus-data-keys-panel.component.html
index a38b7e4dda..048ee94553 100644
--- a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-data-keys-panel/modbus-data-keys-panel.component.html
+++ b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-data-keys-panel/modbus-data-keys-panel.component.html
@@ -89,6 +89,7 @@
                           matInput
                           type="number"
                           min="1"
+                          max="50000"
                           name="value"
                           formControlName="objectsCount"
                           placeholder="{{ 'gateway.set' | translate }}"
@@ -101,7 +102,7 @@
                     <div class="fixed-title-width" translate>gateway.address</div>
                     <div class="tb-flex no-gap">
                       <mat-form-field class="tb-flex no-gap" appearance="outline" subscriptSizing="dynamic">
-                        <input matInput type="number" min="0" name="value" formControlName="address" placeholder="{{ 'gateway.set' | translate }}"/>
+                        <input matInput type="number" min="0" max="50000" name="value" formControlName="address" placeholder="{{ 'gateway.set' | translate }}"/>
                       </mat-form-field>
                     </div>
                   </div>
diff --git a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-security-config/modbus-security-config.component.ts b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-security-config/modbus-security-config.component.ts
index f056c9c92f..1e58cb4a40 100644
--- a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-security-config/modbus-security-config.component.ts
+++ b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-security-config/modbus-security-config.component.ts
@@ -138,7 +138,7 @@ export class ModbusSecurityConfigComponent implements ControlValueAccessor, Vali
     this.securityConfigFormGroup.valueChanges.pipe(
       takeUntil(this.destroy$)
     ).subscribe((value: ModbusSecurity) => {
-      this.onChange(value);
+      this.onChange(this.disabled ? {} : value);
       this.onTouched();
     });
   }
diff --git a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-config/modbus-slave-config.component.html b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-config/modbus-slave-config.component.html
index 4b0789fb4c..41a7d2aee7 100644
--- a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-config/modbus-slave-config.component.html
+++ b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-config/modbus-slave-config.component.html
@@ -102,7 +102,8 @@
       <div class="tb-flex no-gap">
         <mat-form-field class="tb-flex no-gap" appearance="outline" subscriptSizing="dynamic">
           <mat-select formControlName="method">
-            <mat-option *ngFor="let method of modbusMethodTypes" [value]="method">{{ ModbusMethodLabelsMap.get(method) }}</mat-option>
+            <mat-option *ngFor="let method of slaveConfigFormGroup.get('type').value === ModbusProtocolType.Serial ? modbusSerialMethodTypes : modbusMethodTypes"
+                        [value]="method">{{ ModbusMethodLabelsMap.get(method) }}</mat-option>
           </mat-select>
         </mat-form-field>
       </div>
diff --git a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-config/modbus-slave-config.component.ts b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-config/modbus-slave-config.component.ts
index f1234ccfb1..d328a97baf 100644
--- a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-config/modbus-slave-config.component.ts
+++ b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-config/modbus-slave-config.component.ts
@@ -33,6 +33,7 @@ import {
   ModbusProtocolLabelsMap,
   ModbusProtocolType,
   ModbusRegisterValues,
+  ModbusSerialMethodType,
   ModbusSlave,
   noLeadTrailSpacesRegex,
   PortLimits,
@@ -90,6 +91,7 @@ export class ModbusSlaveConfigComponent implements ControlValueAccessor, Validat
 
   readonly modbusProtocolTypes = Object.values(ModbusProtocolType);
   readonly modbusMethodTypes = Object.values(ModbusMethodType);
+  readonly modbusSerialMethodTypes = Object.values(ModbusSerialMethodType);
   readonly modbusOrderType = Object.values(ModbusOrderType);
   readonly ModbusProtocolType = ModbusProtocolType;
   readonly serialSpecificControlKeys = ['serialPort', 'baudrate'];
@@ -107,7 +109,7 @@ export class ModbusSlaveConfigComponent implements ControlValueAccessor, Validat
       host: ['', [Validators.required, Validators.pattern(noLeadTrailSpacesRegex)]],
       port: [null, [Validators.required, Validators.min(PortLimits.MIN), Validators.max(PortLimits.MAX)]],
       serialPort: ['', [Validators.required, Validators.pattern(noLeadTrailSpacesRegex)]],
-      method: [ModbusMethodType.SOCKET, []],
+      method: [ModbusMethodType.RTU, []],
       unitId: [null, [Validators.required]],
       baudrate: [null, []],
       deviceName: ['', [Validators.required, Validators.pattern(noLeadTrailSpacesRegex)]],
@@ -133,7 +135,7 @@ export class ModbusSlaveConfigComponent implements ControlValueAccessor, Validat
         value.port = value.serialPort;
         delete value.serialPort;
       }
-      this.onChange(value);
+      this.onChange(this.slaveConfigFormGroup.get('sendDataToThingsBoard').value ? value : {} as SlaveConfig);
       this.onTouched();
     });
 
@@ -226,7 +228,7 @@ export class ModbusSlaveConfigComponent implements ControlValueAccessor, Validat
     let slaveState: ModbusSlave = {
       host: host ?? '',
       type: type ?? ModbusProtocolType.TCP,
-      method: method ?? ModbusMethodType.SOCKET,
+      method: method ?? ModbusMethodType.RTU,
       unitId: unitId ?? null,
       deviceName: deviceName ?? '',
       deviceType: deviceType ?? '',
diff --git a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-dialog/modbus-slave-dialog.component.html b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-dialog/modbus-slave-dialog.component.html
index 3ac441447c..d3c06aeb4b 100644
--- a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-dialog/modbus-slave-dialog.component.html
+++ b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-dialog/modbus-slave-dialog.component.html
@@ -124,7 +124,8 @@
             <div class="tb-flex no-gap">
               <mat-form-field class="tb-flex no-gap" appearance="outline" subscriptSizing="dynamic">
                 <mat-select formControlName="method">
-                  <mat-option *ngFor="let method of modbusMethodTypes" [value]="method">{{ ModbusMethodLabelsMap.get(method) }}</mat-option>
+                  <mat-option *ngFor="let method of slaveConfigFormGroup.get('type').value === ModbusProtocolType.Serial ? modbusSerialMethodTypes : modbusMethodTypes"
+                              [value]="method">{{ ModbusMethodLabelsMap.get(method) }}</mat-option>
                 </mat-select>
               </mat-form-field>
             </div>
@@ -143,7 +144,9 @@
             <div class="fixed-title-width" translate>gateway.bytesize</div>
             <div class="tb-flex no-gap">
               <mat-form-field class="tb-flex no-gap" appearance="outline" subscriptSizing="dynamic">
-                <input matInput type="number" min="0" name="value" formControlName="bytesize" placeholder="{{ 'gateway.set' | translate }}"/>
+                <mat-select formControlName="bytesize">
+                  <mat-option *ngFor="let size of modbusByteSizes" [value]="size">{{ size }}</mat-option>
+                </mat-select>
               </mat-form-field>
             </div>
           </div>
@@ -159,7 +162,9 @@
             <div class="fixed-title-width" translate>gateway.parity</div>
             <div class="tb-flex no-gap">
               <mat-form-field class="tb-flex no-gap" appearance="outline" subscriptSizing="dynamic">
-                <input matInput name="value" formControlName="parity" placeholder="{{ 'gateway.set' | translate }}"/>
+                <mat-select formControlName="bytesize">
+                  <mat-option *ngFor="let parity of modbusParities" [value]="parity">{{ ModbusParityLabelsMap.get(parity) }}</mat-option>
+                </mat-select>
               </mat-form-field>
             </div>
           </div>
@@ -274,7 +279,7 @@
                   </mat-slide-toggle>
                 </mat-panel-title>
               </mat-expansion-panel-header>
-              <tb-modbus-security-config formControlName="security"></tb-modbus-security-config>
+              <tb-modbus-security-config formControlName="security" [disabled]="!showSecurityControl.value" ></tb-modbus-security-config>
             </mat-expansion-panel>
             <div class="tb-form-row" fxLayoutAlign="space-between center">
               <mat-slide-toggle class="mat-slide" formControlName="retries">
@@ -332,7 +337,6 @@
           </div>
         </mat-expansion-panel>
         <div class="tb-form-panel stroked">
-          <div class="tb-form-panel-title" translate>gateway.values</div>
           <tb-modbus-values [singleMode]="true" formControlName="values"></tb-modbus-values>
         </div>
       </div>
diff --git a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-dialog/modbus-slave-dialog.component.ts b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-dialog/modbus-slave-dialog.component.ts
index 006ae7a482..f0c8c2bd45 100644
--- a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-dialog/modbus-slave-dialog.component.ts
+++ b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/connectors-configuration/modbus/modbus-slave-dialog/modbus-slave-dialog.component.ts
@@ -25,11 +25,15 @@ import {
 } from '@angular/forms';
 import {
   MappingInfo,
+  ModbusByteSizes,
   ModbusMethodLabelsMap,
   ModbusMethodType,
   ModbusOrderType,
+  ModbusParity,
+  ModbusParityLabelsMap,
   ModbusProtocolLabelsMap,
   ModbusProtocolType,
+  ModbusSerialMethodType,
   noLeadTrailSpacesRegex,
   PortLimits, SlaveConfig,
 } from '@home/components/widget/lib/gateway/gateway-widget.models';
@@ -92,8 +96,12 @@ export class ModbusSlaveDialogComponent extends DialogComponent<ModbusSlaveDialo
 
   readonly modbusProtocolTypes = Object.values(ModbusProtocolType);
   readonly modbusMethodTypes = Object.values(ModbusMethodType);
+  readonly modbusSerialMethodTypes = Object.values(ModbusSerialMethodType);
+  readonly modbusParities = Object.values(ModbusParity);
+  readonly modbusByteSizes = ModbusByteSizes;
   readonly modbusOrderType = Object.values(ModbusOrderType);
   readonly ModbusProtocolType = ModbusProtocolType;
+  readonly ModbusParityLabelsMap = ModbusParityLabelsMap;
   readonly ModbusProtocolLabelsMap = ModbusProtocolLabelsMap;
   readonly ModbusMethodLabelsMap = ModbusMethodLabelsMap;
   readonly modbusHelpLink =
@@ -119,11 +127,11 @@ export class ModbusSlaveDialogComponent extends DialogComponent<ModbusSlaveDialo
       host: ['', [Validators.required, Validators.pattern(noLeadTrailSpacesRegex)]],
       port: [null, [Validators.required, Validators.min(PortLimits.MIN), Validators.max(PortLimits.MAX)]],
       serialPort: ['', [Validators.required, Validators.pattern(noLeadTrailSpacesRegex)]],
-      method: [ModbusMethodType.SOCKET, []],
+      method: [ModbusMethodType.RTU, []],
       baudrate: [null, []],
       stopbits: [null, []],
-      bytesize: [null, []],
-      parity: [null, []],
+      bytesize: [ModbusByteSizes[0], []],
+      parity: [ModbusParity.None, []],
       strict: [false, []],
       unitId: [null, [Validators.required]],
       deviceName: ['', [Validators.required, Validators.pattern(noLeadTrailSpacesRegex)]],
@@ -180,6 +188,7 @@ export class ModbusSlaveDialogComponent extends DialogComponent<ModbusSlaveDialo
         slaveResult.port = slaveResult.serialPort;
       }
       delete slaveResult.serialPort;
+      slaveResult.security = this.showSecurityControl.value ? slaveResult.security : {};
       this.dialogRef.close(slaveResult);
     }
   }
diff --git a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/gateway-widget.models.ts b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/gateway-widget.models.ts
index 1204ba087a..3402c09450 100644
--- a/ui-ngx/src/app/modules/home/components/widget/lib/gateway/gateway-widget.models.ts
+++ b/ui-ngx/src/app/modules/home/components/widget/lib/gateway/gateway-widget.models.ts
@@ -769,10 +769,32 @@ export enum ModbusMethodType {
   RTU = 'rtu',
 }
 
-export const ModbusMethodLabelsMap = new Map<ModbusMethodType, string>(
+export enum ModbusSerialMethodType {
+  RTU = 'rtu',
+  ASCII = 'ascii',
+}
+
+export const ModbusMethodLabelsMap = new Map<ModbusMethodType | ModbusSerialMethodType, string>(
   [
     [ModbusMethodType.SOCKET, 'Socket'],
     [ModbusMethodType.RTU, 'RTU'],
+    [ModbusSerialMethodType.ASCII, 'ASCII'],
+  ]
+);
+
+export const ModbusByteSizes = [5, 6, 7 ,8];
+
+export enum ModbusParity {
+  Even = 'E',
+  Odd = 'O',
+  None = 'N'
+}
+
+export const ModbusParityLabelsMap = new Map<ModbusParity, string>(
+  [
+    [ModbusParity.Even, 'Even'],
+    [ModbusParity.Odd, 'Odd'],
+    [ModbusParity.None, 'None'],
   ]
 );
 
@@ -872,7 +894,7 @@ export const ModbusKeysDeleteKeyTranslationsMap = new Map<ModbusValueKey, string
     [ModbusValueKey.ATTRIBUTES, 'gateway.delete-attribute'],
     [ModbusValueKey.TIMESERIES, 'gateway.delete-timeseries'],
     [ModbusValueKey.ATTRIBUTES_UPDATES, 'gateway.delete-attribute-update'],
-    [ModbusValueKey.RPC_REQUESTS, 'gateway.delete-rpc-requests']
+    [ModbusValueKey.RPC_REQUESTS, 'gateway.delete-rpc-request']
   ]
 );