diff --git a/phosphor-regulators/test/chassis_tests.cpp b/phosphor-regulators/test/chassis_tests.cpp
index c04e917..def281c 100644
--- a/phosphor-regulators/test/chassis_tests.cpp
+++ b/phosphor-regulators/test/chassis_tests.cpp
@@ -19,13 +19,15 @@
 #include "device.hpp"
 #include "i2c_interface.hpp"
 #include "id_map.hpp"
+#include "mock_action.hpp"
 #include "mock_journal.hpp"
+#include "mock_sensors.hpp"
 #include "mock_services.hpp"
 #include "mocked_i2c_interface.hpp"
-#include "pmbus_read_sensor_action.hpp"
 #include "presence_detection.hpp"
 #include "rail.hpp"
 #include "rule.hpp"
+#include "sensor_monitoring.hpp"
 #include "sensors.hpp"
 #include "system.hpp"
 #include "test_utils.hpp"
@@ -361,16 +363,16 @@
 {
     // Test where no devices were specified in constructor
     {
-        // Create mock services.  No logging should occur.
+        // Create mock services.  No Sensors methods should be called.
         MockServices services{};
-        MockJournal& journal = services.getMockJournal();
-        EXPECT_CALL(journal, logDebug(A<const std::string&>())).Times(0);
-        EXPECT_CALL(journal, logError(A<const std::string&>())).Times(0);
+        MockSensors& sensors = services.getMockSensors();
+        EXPECT_CALL(sensors, startRail).Times(0);
+        EXPECT_CALL(sensors, setValue).Times(0);
+        EXPECT_CALL(sensors, endRail).Times(0);
 
         // Create Chassis
-        std::vector<std::unique_ptr<Device>> devices{};
-        std::unique_ptr<Chassis> chassis = std::make_unique<Chassis>(
-            1, defaultInventoryPath, std::move(devices));
+        std::unique_ptr<Chassis> chassis =
+            std::make_unique<Chassis>(1, defaultInventoryPath);
         Chassis* chassisPtr = chassis.get();
 
         // Create System that contains Chassis
@@ -385,57 +387,89 @@
 
     // Test where devices were specified in constructor
     {
-        // Create mock services.  No logging should occur.
+        // Create mock services.  Set Sensors service expectations.
         MockServices services{};
-        MockJournal& journal = services.getMockJournal();
-        EXPECT_CALL(journal, logDebug(A<const std::string&>())).Times(0);
-        EXPECT_CALL(journal, logError(A<const std::string&>())).Times(0);
+        MockSensors& sensors = services.getMockSensors();
+        EXPECT_CALL(sensors, startRail("vdd0",
+                                       "/xyz/openbmc_project/inventory/system/"
+                                       "chassis/motherboard/vdd0_reg",
+                                       defaultInventoryPath))
+            .Times(1);
+        EXPECT_CALL(sensors, startRail("vdd1",
+                                       "/xyz/openbmc_project/inventory/system/"
+                                       "chassis/motherboard/vdd1_reg",
+                                       defaultInventoryPath))
+            .Times(1);
+        EXPECT_CALL(sensors, setValue).Times(0);
+        EXPECT_CALL(sensors, endRail(false)).Times(2);
 
         std::vector<std::unique_ptr<Device>> devices{};
 
-        // Create PMBusReadSensorAction
-        SensorType type{SensorType::iout};
-        uint8_t command = 0x8C;
-        pmbus_utils::SensorDataFormat format{
-            pmbus_utils::SensorDataFormat::linear_11};
-        std::optional<int8_t> exponent{};
-        std::unique_ptr<PMBusReadSensorAction> action =
-            std::make_unique<PMBusReadSensorAction>(type, command, format,
-                                                    exponent);
+        // Create Device vdd0_reg
+        {
+            // Create SensorMonitoring for Rail
+            std::unique_ptr<MockAction> action = std::make_unique<MockAction>();
+            EXPECT_CALL(*action, execute).Times(1).WillOnce(Return(true));
+            std::vector<std::unique_ptr<Action>> actions{};
+            actions.emplace_back(std::move(action));
+            std::unique_ptr<SensorMonitoring> sensorMonitoring =
+                std::make_unique<SensorMonitoring>(std::move(actions));
 
-        // Create mock I2CInterface.  A two-byte read should occur.
-        std::unique_ptr<i2c::MockedI2CInterface> i2cInterface =
-            std::make_unique<i2c::MockedI2CInterface>();
-        EXPECT_CALL(*i2cInterface, isOpen).Times(1).WillOnce(Return(true));
-        EXPECT_CALL(*i2cInterface, read(TypedEq<uint8_t>(0x8C), A<uint16_t&>()))
-            .Times(1);
+            // Create Rail
+            std::unique_ptr<Configuration> configuration{};
+            std::unique_ptr<Rail> rail = std::make_unique<Rail>(
+                "vdd0", std::move(configuration), std::move(sensorMonitoring));
 
-        // Create SensorMonitoring
-        std::vector<std::unique_ptr<Action>> actions{};
-        actions.emplace_back(std::move(action));
-        std::unique_ptr<SensorMonitoring> sensorMonitoring =
-            std::make_unique<SensorMonitoring>(std::move(actions));
+            // Create Device
+            std::unique_ptr<i2c::I2CInterface> i2cInterface =
+                createI2CInterface();
+            std::unique_ptr<PresenceDetection> presenceDetection{};
+            std::unique_ptr<Configuration> deviceConfiguration{};
+            std::vector<std::unique_ptr<Rail>> rails{};
+            rails.emplace_back(std::move(rail));
+            std::unique_ptr<Device> device = std::make_unique<Device>(
+                "vdd0_reg", true,
+                "/xyz/openbmc_project/inventory/system/chassis/motherboard/"
+                "vdd0_reg",
+                std::move(i2cInterface), std::move(presenceDetection),
+                std::move(deviceConfiguration), std::move(rails));
+            devices.emplace_back(std::move(device));
+        }
 
-        // Create Rail
-        std::vector<std::unique_ptr<Rail>> rails{};
-        std::unique_ptr<Configuration> configuration{};
-        std::unique_ptr<Rail> rail = std::make_unique<Rail>(
-            "vdd0", std::move(configuration), std::move(sensorMonitoring));
-        rails.emplace_back(std::move(rail));
+        // Create Device vdd1_reg
+        {
+            // Create SensorMonitoring for Rail
+            std::unique_ptr<MockAction> action = std::make_unique<MockAction>();
+            EXPECT_CALL(*action, execute).Times(1).WillOnce(Return(true));
+            std::vector<std::unique_ptr<Action>> actions{};
+            actions.emplace_back(std::move(action));
+            std::unique_ptr<SensorMonitoring> sensorMonitoring =
+                std::make_unique<SensorMonitoring>(std::move(actions));
 
-        // Create Device
-        std::unique_ptr<PresenceDetection> presenceDetection{};
-        std::unique_ptr<Configuration> deviceConfiguration{};
-        std::unique_ptr<Device> device = std::make_unique<Device>(
-            "reg1", true,
-            "/xyz/openbmc_project/inventory/system/chassis/motherboard/reg1",
-            std::move(i2cInterface), std::move(presenceDetection),
-            std::move(deviceConfiguration), std::move(rails));
+            // Create Rail
+            std::unique_ptr<Configuration> configuration{};
+            std::unique_ptr<Rail> rail = std::make_unique<Rail>(
+                "vdd1", std::move(configuration), std::move(sensorMonitoring));
 
-        // Create Chassis
-        devices.emplace_back(std::move(device));
+            // Create Device
+            std::unique_ptr<i2c::I2CInterface> i2cInterface =
+                createI2CInterface();
+            std::unique_ptr<PresenceDetection> presenceDetection{};
+            std::unique_ptr<Configuration> deviceConfiguration{};
+            std::vector<std::unique_ptr<Rail>> rails{};
+            rails.emplace_back(std::move(rail));
+            std::unique_ptr<Device> device = std::make_unique<Device>(
+                "vdd1_reg", true,
+                "/xyz/openbmc_project/inventory/system/chassis/motherboard/"
+                "vdd1_reg",
+                std::move(i2cInterface), std::move(presenceDetection),
+                std::move(deviceConfiguration), std::move(rails));
+            devices.emplace_back(std::move(device));
+        }
+
+        // Create Chassis that contains Devices
         std::unique_ptr<Chassis> chassis = std::make_unique<Chassis>(
-            1, defaultInventoryPath, std::move(devices));
+            2, defaultInventoryPath, std::move(devices));
         Chassis* chassisPtr = chassis.get();
 
         // Create System that contains Chassis