diff --git a/src/hardware/scpi-pps/api.c b/src/hardware/scpi-pps/api.c
index bd7e6d6e..4c5e9afc 100644
--- a/src/hardware/scpi-pps/api.c
+++ b/src/hardware/scpi-pps/api.c
@@ -320,7 +320,6 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 	struct pps_channel *pch;
 	double d;
 	int ret;
-	const char *s;
 
 	if (!sdi)
 		return SR_ERR_ARG;
@@ -333,8 +332,10 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 		switch (key) {
 		/* No channel group: global options. */
 		case SR_CONF_OUTPUT_ENABLED:
-			s = g_variant_get_boolean(data) ? "ON" : "OFF";
-			ret = scpi_cmd(sdi, SCPI_CMD_SET_OUTPUT_ENABLED, s);
+			if (g_variant_get_boolean(data))
+				ret = scpi_cmd(sdi, SCPI_CMD_SET_OUTPUT_ENABLE);
+			else
+				ret = scpi_cmd(sdi, SCPI_CMD_SET_OUTPUT_DISABLE);
 			break;
 		case SR_CONF_OUTPUT_VOLTAGE_MAX:
 			d = g_variant_get_double(data);
@@ -345,8 +346,10 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 			ret = scpi_cmd(sdi, SCPI_CMD_SET_CURRENT_MAX, d);
 			break;
 		case SR_CONF_OVER_TEMPERATURE_PROTECTION:
-			s = g_variant_get_boolean(data) ? "ON" : "OFF";
-			ret = scpi_cmd(sdi, SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION, s);
+			if (g_variant_get_boolean(data))
+				ret = scpi_cmd(sdi, SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_ENABLE);
+			else
+				ret = scpi_cmd(sdi, SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_DISABLE);
 			break;
 		default:
 			ret = SR_ERR_NA;
@@ -357,8 +360,10 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 		pch = ch->priv;
 		switch (key) {
 		case SR_CONF_OUTPUT_ENABLED:
-			s = g_variant_get_boolean(data) ? "ON" : "OFF";
-			ret = scpi_cmd(sdi, SCPI_CMD_SET_OUTPUT_ENABLED, pch->hwname, s);
+			if (g_variant_get_boolean(data))
+				ret = scpi_cmd(sdi, SCPI_CMD_SET_OUTPUT_ENABLE, pch->hwname);
+			else
+				ret = scpi_cmd(sdi, SCPI_CMD_SET_OUTPUT_DISABLE, pch->hwname);
 			break;
 		case SR_CONF_OUTPUT_VOLTAGE_MAX:
 			d = g_variant_get_double(data);
@@ -369,9 +374,12 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 			ret = scpi_cmd(sdi, SCPI_CMD_SET_CURRENT_MAX, pch->hwname, d);
 			break;
 		case SR_CONF_OVER_VOLTAGE_PROTECTION_ENABLED:
-			s = g_variant_get_boolean(data) ? "ON" : "OFF";
-			ret = scpi_cmd(sdi, SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_ENABLED,
-					pch->hwname, s);
+			if (g_variant_get_boolean(data))
+				ret = scpi_cmd(sdi, SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_ENABLE,
+						pch->hwname);
+			else
+				ret = scpi_cmd(sdi, SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_DISABLE,
+						pch->hwname);
 			break;
 		case SR_CONF_OVER_VOLTAGE_PROTECTION_THRESHOLD:
 			d = g_variant_get_double(data);
@@ -379,9 +387,12 @@ static int config_set(uint32_t key, GVariant *data, const struct sr_dev_inst *sd
 					pch->hwname, d);
 			break;
 		case SR_CONF_OVER_CURRENT_PROTECTION_ENABLED:
-			s = g_variant_get_boolean(data) ? "ON" : "OFF";
-			ret = scpi_cmd(sdi, SCPI_CMD_SET_OVER_CURRENT_PROTECTION_ENABLED,
-					pch->hwname, s);
+			if (g_variant_get_boolean(data))
+				ret = scpi_cmd(sdi, SCPI_CMD_SET_OVER_CURRENT_PROTECTION_ENABLE,
+						pch->hwname);
+			else
+				ret = scpi_cmd(sdi, SCPI_CMD_SET_OVER_CURRENT_PROTECTION_DISABLE,
+						pch->hwname);
 			break;
 		case SR_CONF_OVER_CURRENT_PROTECTION_THRESHOLD:
 			d = g_variant_get_double(data);
diff --git a/src/hardware/scpi-pps/profiles.c b/src/hardware/scpi-pps/profiles.c
index efd87193..deb200dc 100644
--- a/src/hardware/scpi-pps/profiles.c
+++ b/src/hardware/scpi-pps/profiles.c
@@ -91,17 +91,21 @@ struct scpi_command rigol_dp800_cmd[] = {
 	{ SCPI_CMD_GET_CURRENT_MAX, ":SOUR%s:CURR?" },
 	{ SCPI_CMD_SET_CURRENT_MAX, ":SOUR%s:CURR %.6f" },
 	{ SCPI_CMD_GET_OUTPUT_ENABLED, ":OUTP? CH%s" },
-	{ SCPI_CMD_SET_OUTPUT_ENABLED, ":OUTP CH%s,%s" },
+	{ SCPI_CMD_SET_OUTPUT_ENABLE, ":OUTP CH%s,ON" },
+	{ SCPI_CMD_SET_OUTPUT_DISABLE, ":OUTP CH%s,OFF" },
 	{ SCPI_CMD_GET_OUTPUT_REGULATION, ":OUTP:MODE? CH%s" },
 	{ SCPI_CMD_GET_OVER_TEMPERATURE_PROTECTION, ":SYST:OTP?" },
-	{ SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION, ":SYST:OTP %s" },
+	{ SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_ENABLE, ":SYST:OTP ON" },
+	{ SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_DISABLE, ":SYST:OTP OFF" },
 	{ SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_ENABLED, ":OUTP:OVP? CH%s" },
-	{ SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_ENABLED, ":OUTP:OVP CH%s,%s" },
+	{ SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_ENABLE, ":OUTP:OVP CH%s,ON" },
+	{ SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_DISABLE, ":OUTP:OVP CH%s,OFF" },
 	{ SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_ACTIVE, ":OUTP:OVP:QUES? CH%s" },
 	{ SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_THRESHOLD, ":OUTP:OVP:VAL? CH%s" },
 	{ SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_THRESHOLD, ":OUTP:OVP:VAL CH%s,%.6f" },
 	{ SCPI_CMD_GET_OVER_CURRENT_PROTECTION_ENABLED, ":OUTP:OCP? CH%s" },
-	{ SCPI_CMD_SET_OVER_CURRENT_PROTECTION_ENABLED, ":OUTP:OCP CH%s,%s" },
+	{ SCPI_CMD_SET_OVER_CURRENT_PROTECTION_ENABLE, ":OUTP:OCP CH%s,ON" },
+	{ SCPI_CMD_SET_OVER_CURRENT_PROTECTION_DISABLE, ":OUTP:OCP CH%s,OFF" },
 	{ SCPI_CMD_GET_OVER_CURRENT_PROTECTION_ACTIVE, ":OUTP:OCP:QUES? CH%s" },
 	{ SCPI_CMD_GET_OVER_CURRENT_PROTECTION_THRESHOLD, ":OUTP:OCP:VAL? CH%s" },
 	{ SCPI_CMD_SET_OVER_CURRENT_PROTECTION_THRESHOLD, ":OUTP:OCP:VAL CH%s,%.6f" },
@@ -128,7 +132,8 @@ struct channel_group_spec hp_6632b_cg[] = {
 
 struct scpi_command hp_6632b_cmd[] = {
 	{ SCPI_CMD_GET_OUTPUT_ENABLED, "OUTP:STAT?" },
-	{ SCPI_CMD_SET_OUTPUT_ENABLED, "OUTP:STAT %s" },
+	{ SCPI_CMD_SET_OUTPUT_ENABLE, "OUTP:STAT ON" },
+	{ SCPI_CMD_SET_OUTPUT_DISABLE, "OUTP:STAT OFF" },
 	{ SCPI_CMD_GET_MEAS_VOLTAGE, ":MEAS:VOLT?" },
 	{ SCPI_CMD_GET_MEAS_CURRENT, ":MEAS:CURR?" },
 	{ SCPI_CMD_GET_VOLTAGE_MAX, ":SOUR:VOLT?" },
diff --git a/src/hardware/scpi-pps/protocol.h b/src/hardware/scpi-pps/protocol.h
index 552d5030..597ed09f 100644
--- a/src/hardware/scpi-pps/protocol.h
+++ b/src/hardware/scpi-pps/protocol.h
@@ -37,17 +37,21 @@ enum pps_scpi_cmds {
 	SCPI_CMD_GET_CURRENT_MAX,
 	SCPI_CMD_SET_CURRENT_MAX,
 	SCPI_CMD_GET_OUTPUT_ENABLED,
-	SCPI_CMD_SET_OUTPUT_ENABLED,
+	SCPI_CMD_SET_OUTPUT_ENABLE,
+	SCPI_CMD_SET_OUTPUT_DISABLE,
 	SCPI_CMD_GET_OUTPUT_REGULATION,
 	SCPI_CMD_GET_OVER_TEMPERATURE_PROTECTION,
-	SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION,
+	SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_ENABLE,
+	SCPI_CMD_SET_OVER_TEMPERATURE_PROTECTION_DISABLE,
 	SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_ENABLED,
-	SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_ENABLED,
+	SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_ENABLE,
+	SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_DISABLE,
 	SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_ACTIVE,
 	SCPI_CMD_GET_OVER_VOLTAGE_PROTECTION_THRESHOLD,
 	SCPI_CMD_SET_OVER_VOLTAGE_PROTECTION_THRESHOLD,
 	SCPI_CMD_GET_OVER_CURRENT_PROTECTION_ENABLED,
-	SCPI_CMD_SET_OVER_CURRENT_PROTECTION_ENABLED,
+	SCPI_CMD_SET_OVER_CURRENT_PROTECTION_ENABLE,
+	SCPI_CMD_SET_OVER_CURRENT_PROTECTION_DISABLE,
 	SCPI_CMD_GET_OVER_CURRENT_PROTECTION_ACTIVE,
 	SCPI_CMD_GET_OVER_CURRENT_PROTECTION_THRESHOLD,
 	SCPI_CMD_SET_OVER_CURRENT_PROTECTION_THRESHOLD,