diff --git a/main.c b/main.c
index 0013be5..6f49dcf 100644
--- a/main.c
+++ b/main.c
@@ -304,16 +304,15 @@ void main(void)
 
 	// start getting all PZEM-004T measurements from all meters
 	struct sensor_pzem_measurement_t pzem_measurements[2][SENSOR_PZEM_MAX]; // PZEM-004T measurements (2 meters, all measurements)
-	uint8_t pzem_id = 0; // PZEM-004T meter index (add to prefix)
-	sensor_pzem_measurement_request(0xc0a80100+pzem_id, 0); // request first measurement
-	(void)pzem_measurements[pzem_id][0];
+	uint8_t pzem_meter = 0; // PZEM-004T meter index (add to prefix)
+	uint8_t pzem_measurement = 0; // PZEM-004T measurement index (matches the type)
+	sensor_pzem_measurement_request(0xc0a80100+pzem_meter, pzem_measurement); // request first measurement
 
 	// start getting all SDM120 measurements from all meters
 	float sdm120_measurements[2][SENSOR_SDM120_MEASUREMENT_MAX]; // SDM120 measurements (2 meters, all measurements)
 	uint8_t sdm120_meter = 0; // SDM120 meter index (add to 1 to get ID)
 	uint8_t sdm120_measurement = 0; // SDM120 measurement index
 	sensor_sdm120_measurement_request(1+sdm120_meter, sdm120_measurement); // request first measurement
-	(void)sdm120_measurements[sdm120_meter][sdm120_measurement];
 
 	while (true) { // infinite loop
 		iwdg_reset(); // kick the dog
@@ -354,20 +353,19 @@ void main(void)
 				fprintf(stderr,"unknown measurement type: %u\n", measurement.type);
 				while (true); // unhandled error
 			}
-			pzem_measurements[pzem_id][measurement.type] = measurement; // save measurement (the type matches the index)
 			if (measurement.valid) { // only show valid measurement
 				switch (measurement.type) {
 				case SENSOR_PZEM_VOLTAGE:
-					printf("PZEM-004T meter %u voltage: %.01f V\n", pzem_id, measurement.value.voltage); // display measurement
+					printf("PZEM-004T meter %u voltage: %.01f V\n", pzem_meter, measurement.value.voltage); // display measurement
 					break;
 				case SENSOR_PZEM_CURRENT:
-					printf("PZEM-004T meter %u current: %.02f A\n", pzem_id, measurement.value.current);
+					printf("PZEM-004T meter %u current: %.02f A\n", pzem_meter, measurement.value.current);
 					break;
 				case SENSOR_PZEM_POWER:
-					printf("PZEM-004T meter %u power: %.00f W\n", pzem_id, measurement.value.power);
+					printf("PZEM-004T meter %u power: %.00f W\n", pzem_meter, measurement.value.power);
 					break;
 				case SENSOR_PZEM_ENERGY:
-					printf("PZEM-004T meter %u energy: %lu Wh\n", pzem_id, measurement.value.energy);
+					printf("PZEM-004T meter %u energy: %lu Wh\n", pzem_meter, measurement.value.energy);
 					break;
 /* not used for this application
 				case SENSOR_PZEM_ADDRESS:
@@ -380,16 +378,24 @@ void main(void)
 				default:
 					break;
 				}
-				if (measurement.type<SENSOR_PZEM_MAX-1) { // not all measurement types requested
-					 sensor_pzem_measurement_request(0xc0a80100+pzem_id, measurement.type+1); // request next measurement
+				if (measurement.type!=pzem_measurement) {
+					fprintf(stderr, "PZEM-004T measurement mismatch: expected %u, got %u\n", pzem_measurement, measurement.type);
+					sensor_pzem_measurement_request(0xc0a80100+pzem_meter, pzem_measurement); // request same measurement
+				} else if (pzem_measurement<SENSOR_PZEM_MAX-1) { // not all measurement types requested
+					pzem_measurements[pzem_meter][pzem_measurement] = measurement; // save measurement (the type matches the index)
+					pzem_measurement++; // go to next measurement
+					sensor_pzem_measurement_request(0xc0a80100+pzem_meter, pzem_measurement); // request next measurement
 				} else { // all measurement types requested
-					pzem_id++; // got to next meter
-					if (pzem_id<LENGTH(pzem_measurements)) { // ensure next meter exists
-						sensor_pzem_measurement_request(0xc0a80100+pzem_id, 0); // request measurement for next meter
+					pzem_measurements[pzem_meter][pzem_measurement] = measurement; // save measurement (the type matches the index)
+					pzem_meter++; // got to next meter
+					pzem_measurement = 0; // restart measurements
+					if (pzem_meter<LENGTH(pzem_measurements)) { // ensure next meter exists
+						sensor_pzem_measurement_request(0xc0a80100+pzem_meter, pzem_measurement); // request measurement for next meter
 					}
 				}
 			} else { // measurement not valid
-				sensor_pzem_measurement_request(0xc0a80100+pzem_id, measurement.type+1); // request same measurement
+				fprintf(stderr, "PZEM-004T measurement invalid\n");
+				sensor_pzem_measurement_request(0xc0a80100+pzem_meter, pzem_measurement); // request same measurement
 			}
 		}
 		while (sensor_sdm120_measurement_received) { // measurement from electricity meter received