diff --git a/main.c b/main.c
index c8ce75a..39db399 100644
--- a/main.c
+++ b/main.c
@@ -55,12 +55,7 @@
 volatile bool rtc_internal_tick_flag = false; /**< flag set when internal RTC ticked */
 /** @} */
 
-/** @defgroup main_timer timer used to periodically query the meter measurements
- *  @{
- */
-#define MAIN_TIMER 4 /**< timer number */
-#define MAIN_PERIOD 10.0 /**< period in seconds to query meter measurements */
-/** @} */
+#define QUERY_PERIOD 10 /**< period in seconds to query meter measurements */
 
 
 int _write(int file, char *ptr, int len)
@@ -275,20 +270,6 @@ void main(void)
 	radio_esp8266_setup();
 	printf("OK\n");
 
-	// setup timer to periodically query meter measurements
-	printf("setup query timer (%.0fs): ", MAIN_PERIOD);
-	rcc_periph_clock_enable(RCC_TIM(MAIN_TIMER)); // enable clock for timer block
-	timer_reset(TIM(MAIN_TIMER)); // reset timer state
-	timer_set_mode(TIM(MAIN_TIMER), TIM_CR1_CKD_CK_INT, TIM_CR1_CMS_EDGE, TIM_CR1_DIR_UP); // set timer mode, use undivided timer clock,edge alignment (simple count), and count up
-	timer_set_prescaler(TIM(MAIN_TIMER), 0xffff); // set the prescaler so this 16 bits timer allows to wait for ~60s ( (2**16)/(2**16)/72E6=59.65s )
-	timer_set_period(TIM(MAIN_TIMER), MAIN_PERIOD*(rcc_ahb_frequency/(TIM_PSC(TIM(MAIN_TIMER))+1))); // set period for meter measurements queries
-	timer_set_counter(TIM(MAIN_TIMER), 0); // reset timer counter to get preset waiting time
-	timer_clear_flag(TIM(MAIN_TIMER), TIM_SR_UIF); // clear flag
-	timer_enable_irq(TIM(MAIN_TIMER), TIM_DIER_UIE); // enable update interrupt for timer (timer overflows when period is reached)
-	//nvic_enable_irq(NVIC_TIM_IRQ(MAIN_TIMER)); // allow interrupt for timer just to wake up
-	timer_enable_counter(TIM(MAIN_TIMER)); // start timer for periodic queries
-	printf("OK\n");
-
 #if !(DEBUG)
 	//setup watchdog to reset in case we get stuck (i.e. when an error occurred)
 	printf("setup watchdog (%.2fs): ",WATCHDOG_PERIOD/1000.0);
@@ -489,6 +470,17 @@ void main(void)
 			if ((ticks_time%(60))==0) { // one minute passed
 				printf("uptime: %lu.%02lu:%02lu:%02lu\n", ticks_time/(60*60*24), (ticks_time/(60*60))%24, (ticks_time%(60*60))/60, (ticks_time%60)); // display external time
 			}
+			if ((ticks_time%(QUERY_PERIOD))==0) { // query period passed
+				printf("query meter measurements (%lu.%02lu:%02lu:%02lu)\n", ticks_time/(60*60*24), (ticks_time/(60*60))%24, (ticks_time%(60*60))/60, (ticks_time%60));
+				// start getting all PZEM-004T measurements from all meters
+				pzem_meter = 0; // reset PZEM meter number
+				pzem_measurement = 0; // reset PZEM measurement index
+				sensor_pzem_measurement_request(0xc0a80100+pzem_meter, pzem_measurement); // request first measurement
+				// start getting all SDM120 measurements from all meters
+				sdm120_meter = 0; // reset SDM120 meter number
+				sdm120_measurement = 0; // reset SDM120 measurement index
+				sensor_sdm120_measurement_request(1+sdm120_meter, sdm120_measurement); // request first measurement
+			}
 		}
 		while (pzem_meter>=LENGTH(pzem_measurements) && sdm120_meter>=LENGTH(sdm120_measurements)) { // all measurements received for all meter
 			action = true; // action has been performed
@@ -600,19 +592,6 @@ void main(void)
 			sdm120_meter = 0; // reset meter
 
 		}
-		while (timer_get_flag(TIM(MAIN_TIMER), TIM_SR_UIF)) { // timer update event -> query measurements
-			timer_clear_flag(TIM(MAIN_TIMER), TIM_SR_UIF); // clear flag
-			action = true; // action has been performed
-			printf("query meter measurements (%lu.%02lu:%02lu:%02lu)\n", ticks_time/(60*60*24), (ticks_time/(60*60))%24, (ticks_time%(60*60))/60, (ticks_time%60));
-			// start getting all PZEM-004T measurements from all meters
-			pzem_meter = 0; // reset PZEM meter number
-			pzem_measurement = 0; // reset PZEM measurement index
-			sensor_pzem_measurement_request(0xc0a80100+pzem_meter, pzem_measurement); // request first measurement
-			// start getting all SDM120 measurements from all meters
-			sdm120_meter = 0; // reset SDM120 meter number
-			sdm120_measurement = 0; // reset SDM120 measurement index
-			sensor_sdm120_measurement_request(1+sdm120_meter, sdm120_measurement); // request first measurement
-		}
 		if (action) { // go to sleep if nothing had to be done, else recheck for activity
 			action = false;
 		} else {