diff --git a/src/main/java/com/xydl/cac/model/ConditionModel.java b/src/main/java/com/xydl/cac/model/ConditionModel.java
index 954cee2..94f3b05 100644
--- a/src/main/java/com/xydl/cac/model/ConditionModel.java
+++ b/src/main/java/com/xydl/cac/model/ConditionModel.java
@@ -29,4 +29,7 @@ public class ConditionModel {
     Integer pageNum;
     @ApiModelProperty("每页数量")
     Integer pageSize;
+    @ApiModelProperty("每天最大数量")
+    Integer numPerDay;
+
 }
diff --git a/src/main/java/com/xydl/cac/service/DataService.java b/src/main/java/com/xydl/cac/service/DataService.java
index a1d273c..0d1f9e9 100644
--- a/src/main/java/com/xydl/cac/service/DataService.java
+++ b/src/main/java/com/xydl/cac/service/DataService.java
@@ -4,6 +4,7 @@ package com.xydl.cac.service;
 import com.xydl.cac.entity.*;
 import com.xydl.cac.model.*;
 
+import java.text.ParseException;
 import java.util.List;
 import java.util.Map;
 
@@ -13,7 +14,9 @@ public interface DataService {
 
     List<ColumnModel> getDataTableColumns(String tableName) throws Exception;
 
-    OnePage<Map<String, Object>> getDate(NSensor sensor, List<ModevTypePoint> points, ConditionModel model);
+    OnePage<Map<String, Object>> getData(NSensor sensor, List<ModevTypePoint> points, ConditionModel model);
+
+    OnePage<Map<String, Object>> getDataByDate(NSensor sensor, List<ModevTypePoint> points, ConditionModel model, int dayPerPage) throws Exception;
 
     void clearAllBind();
 }
diff --git a/src/main/java/com/xydl/cac/service/impl/DataServiceImpl.java b/src/main/java/com/xydl/cac/service/impl/DataServiceImpl.java
index be2f835..0c72734 100644
--- a/src/main/java/com/xydl/cac/service/impl/DataServiceImpl.java
+++ b/src/main/java/com/xydl/cac/service/impl/DataServiceImpl.java
@@ -7,6 +7,7 @@ import com.xydl.cac.model.OnePage;
 import com.xydl.cac.repository.ModevTypeRepository;
 import com.xydl.cac.service.DataService;
 import com.xydl.cac.util.DataTable;
+import com.xydl.cac.util.DataUtil;
 import com.xydl.cac.util.DateUtil;
 import lombok.extern.slf4j.Slf4j;
 import org.apache.commons.lang3.StringUtils;
@@ -16,7 +17,10 @@ import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
 import javax.annotation.Resource;
+import java.text.ParseException;
+import java.time.temporal.ChronoUnit;
 import java.util.ArrayList;
+import java.util.Date;
 import java.util.List;
 import java.util.Map;
 
@@ -83,7 +87,7 @@ public class DataServiceImpl implements DataService {
     }
 
     @Override
-    public OnePage<Map<String, Object>> getDate(NSensor sensor, List<ModevTypePoint> points, ConditionModel model) {
+    public OnePage<Map<String, Object>> getData(NSensor sensor, List<ModevTypePoint> points, ConditionModel model) {
         String devField = DataTable.getDevidField(sensor.getTableName());
         String timeField = DataTable.getTimeField(sensor.getTableName());
         OnePage result = new OnePage();
@@ -122,6 +126,54 @@ public class DataServiceImpl implements DataService {
         return result;
     }
 
+    @Override
+    public OnePage<Map<String, Object>> getDataByDate(NSensor sensor, List<ModevTypePoint> points, ConditionModel model, int dayPerPage) throws Exception {
+
+        // 处理开始和结束时间
+        Date end = model.getEndTime();
+        if (end == null) {
+            end = new Date();
+        }
+        end = DateUtil.addDay(end, 1);
+        end = DateUtil.getDayZero(end);
+        model.setEndTime(end);
+
+        Date start = model.getStartTime();
+        if (start == null) {
+            start = DateUtil.addMonth(new Date(), -1);
+        }
+        start = DateUtil.getDayZero(start);
+        model.setStartTime(start);
+
+        long daysBetweenDates = DateUtil.getDifferenceInDays(start, end);
+
+        // 本次查询的时间范围
+        ConditionModel newmodel = new ConditionModel();
+        if (daysBetweenDates > dayPerPage) {
+            if (model.getPageNum() > 1) {
+                int p = model.getPageNum() - 1;
+                end = DateUtil.addDay(end, -dayPerPage * p);
+            }
+            newmodel.setEndTime(end);
+            start = DateUtil.addDay(end, -dayPerPage);
+            if (start.compareTo(model.getStartTime()) > 0) {
+                newmodel.setStartTime(start);
+            } else {
+                newmodel.setStartTime(model.getStartTime());
+            }
+        }
+        OnePage<Map<String, Object>> page = this.getData(sensor, points, newmodel);
+
+        // 从数据里每天抽取num条
+        List<Map<String, Object>> content = DataUtil.pickNumPerDay(page.getContent(), model.getNumPerDay());
+        page.setContent(content);
+
+        page.setPageNum(model.getPageNum());
+        page.setPageSize(model.getPageSize());
+        page.setTotal(daysBetweenDates * model.getPageSize());
+        return page;
+    }
+
     @Override
     public void clearAllBind() {
         String sql = "UPDATE n_sensor SET icd_id=null";
diff --git a/src/main/java/com/xydl/cac/service/impl/NSensorServiceImpl.java b/src/main/java/com/xydl/cac/service/impl/NSensorServiceImpl.java
index b4c66a7..816bc92 100644
--- a/src/main/java/com/xydl/cac/service/impl/NSensorServiceImpl.java
+++ b/src/main/java/com/xydl/cac/service/impl/NSensorServiceImpl.java
@@ -166,11 +166,12 @@ public class NSensorServiceImpl implements NSensorService {
             throw new BusinessException("该装置类型" + sensor.getTypeName() + "未配置属性点信息");
         }
 
+        // 获取数据
         SensorDetail<Map<String, Object>> result = this.getData(sensor, points, model);
         return result;
     }
 
-    public SensorDetail<Map<String, Object>> getData(NSensor sensor, List<ModevTypePoint> points, ConditionModel model) {
+    public SensorDetail<Map<String, Object>> getData(NSensor sensor, List<ModevTypePoint> points, ConditionModel model) throws Exception {
         List<ModevTypePoint> pointList = new ArrayList<>();
         for (ModevTypePoint point : points) {
             if (StringUtils.isNotBlank(point.getField())) {
@@ -180,8 +181,18 @@ public class NSensorServiceImpl implements NSensorService {
 
         SensorDetail<Map<String, Object>> result = new SensorDetail();
         result.setSensor(sensor);
-        OnePage<Map<String, Object>> page = dataService.getDate(sensor, pointList, model);
-        result.initFrom(page);
+
+
+        if (model.getNumPerDay() != null && model.getPageSize() > model.getNumPerDay()) {
+            // 按每页几天取数据
+            int dayPerPage = model.getPageSize() / model.getNumPerDay();
+            OnePage<Map<String, Object>> page = dataService.getDataByDate(sensor, pointList, model, dayPerPage);
+            result.initFrom(page);
+        } else {
+            // 按全量取数据
+            OnePage<Map<String, Object>> page = dataService.getData(sensor, pointList, model);
+            result.initFrom(page);
+        }
 
         for (ModevTypePoint point : pointList) {
             List<Object> dataList = new ArrayList<>();
diff --git a/src/main/java/com/xydl/cac/util/DataUtil.java b/src/main/java/com/xydl/cac/util/DataUtil.java
new file mode 100644
index 0000000..a22ca43
--- /dev/null
+++ b/src/main/java/com/xydl/cac/util/DataUtil.java
@@ -0,0 +1,69 @@
+package com.xydl.cac.util;
+
+import java.util.*;
+
+public class DataUtil {
+
+    // 从数据里每天抽取num条
+    public static List<Map<String, Object>> pickNumPerDay(List<Map<String, Object>> source, Integer numPerDay) throws Exception {
+
+        // 按天划分
+        LinkedHashMap<String, List<Map<String, Object>>> map = new LinkedHashMap<>();
+        for (Map<String, Object> item : source) {
+            String time = (String) item.get("acquisitionTime");
+            Date date = DateUtil.parse(time);
+            String day = DateUtil.format(date, "yyyy-MM-dd");
+
+            List<Map<String, Object>> list = map.get(day);
+            if (list == null) {
+                list = new ArrayList<>();
+                list.add(item);
+                map.put(day, list);
+            } else {
+                list.add(item);
+            }
+        }
+
+        // 过滤多余
+        for (List<Map<String, Object>> list : map.values()) {
+            if (list.size() > numPerDay) {
+                reduceOneDaySize(list, numPerDay);
+            }
+        }
+
+        // 合并返回
+        List<Map<String, Object>> result = new ArrayList<>();
+        for (List<Map<String, Object>> list : map.values()) {
+            result.addAll(list);
+        }
+        return result;
+    }
+
+    private static void reduceOneDaySize(List<Map<String, Object>> list, Integer numPerDay) {
+        int m = list.size() / numPerDay;
+        int x = list.size() - numPerDay;
+        if (m == 1) {
+            if (x == 1) {
+                list.remove(0);
+            } else {
+                int idx = 0;
+                while (list.size() > numPerDay) {
+                    if (idx >= list.size()) {
+                        idx = 0;
+                    }
+                    list.remove(idx);
+                    idx++;
+                }
+            }
+        } else {
+            List<Map<String, Object>> newlist = new ArrayList<>();
+            for (int i = 0; i < numPerDay; i++) {
+                int idx = m * (i + 1) - 1;
+                Map<String, Object> item = list.get(idx);
+                newlist.add(item);
+            }
+            list.clear();
+            list.addAll(newlist);
+        }
+    }
+}
diff --git a/src/main/java/com/xydl/cac/util/DateUtil.java b/src/main/java/com/xydl/cac/util/DateUtil.java
index fabb0ce..d9f5b1d 100644
--- a/src/main/java/com/xydl/cac/util/DateUtil.java
+++ b/src/main/java/com/xydl/cac/util/DateUtil.java
@@ -2,6 +2,9 @@ package com.xydl.cac.util;
 
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
+import java.time.LocalDate;
+import java.time.ZoneId;
+import java.time.temporal.ChronoUnit;
 import java.util.Calendar;
 import java.util.Date;
 
@@ -57,6 +60,12 @@ public class DateUtil {
         return df.parse(str);
     }
 
+    public static Date getDayZero(Date date) throws ParseException {
+        SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");
+        String str = df.format(date);
+        return df.parse(str);
+    }
+
     public static Date getMonthZero() throws ParseException {
         SimpleDateFormat df = new SimpleDateFormat("yyyy-MM");
         String str = df.format(new Date());
@@ -80,4 +89,10 @@ public class DateUtil {
         return cal.getTime();
     }
 
+    public static long getDifferenceInDays(Date startDate, Date endDate) {
+        LocalDate startLocalDate = startDate.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();
+        LocalDate endLocalDate = endDate.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();
+        return ChronoUnit.DAYS.between(startLocalDate, endLocalDate);
+    }
+
 }